src/App.tsx

@@ -14,6 +14,8 @@ import MilestoneDetailPage from '@/pages/MilestoneDetailPage'
 import NotificationsPage from '@/pages/NotificationsPage'
 import RoleEditorPage from '@/pages/RoleEditorPage'
 import MonitorPage from '@/pages/MonitorPage'
+import ProposesPage from '@/pages/ProposesPage'
+import ProposeDetailPage from '@/pages/ProposeDetailPage'
 import axios from 'axios'
 
 const WIZARD_PORT = Number(import.meta.env.VITE_WIZARD_PORT) || 18080
@@ -90,6 +92,8 @@ export default function App() {
             <Route path="/projects/:id" element={<ProjectDetailPage />} />
             <Route path="/milestones" element={<MilestonesPage />} />
             <Route path="/milestones/:id" element={<MilestoneDetailPage />} />
+            <Route path="/proposes" element={<ProposesPage />} />
+            <Route path="/proposes/:id" element={<ProposeDetailPage />} />
             <Route path="/notifications" element={<NotificationsPage />} />
             <Route path="/roles" element={<RoleEditorPage />} />
             <Route path="/monitor" element={<MonitorPage />} />

src/components/CreateTaskModal.tsx

@@ -3,11 +3,11 @@ import api from '@/services/api'
 import type { Milestone, Project, Task } from '@/types'
 
 const TASK_TYPES = [
-  { value: 'story', label: 'Story', subtypes: ['feature', 'improvement', 'refactor'] },
+  { value: 'story', label: 'Story', subtypes: ['improvement', 'refactor'] },  // P9.6: 'feature' removed — must come from propose accept
   { value: 'issue', label: 'Issue', subtypes: ['infrastructure', 'performance', 'regression', 'security', 'user_experience', 'defect'] },
-  { value: 'task', label: 'Task', subtypes: ['defect'] },
+  // P7.1: 'task' type removed — defect subtype migrated to issue/defect
   { value: 'test', label: 'Test', subtypes: ['regression', 'security', 'smoke', 'stress'] },
-  { value: 'maintenance', label: 'Maintenance', subtypes: ['deploy', 'release'] },
+  { value: 'maintenance', label: 'Maintenance', subtypes: ['deploy'] },  // P9.6: 'release' removed — controlled via milestone flow
   { value: 'research', label: 'Research', subtypes: [] },
   { value: 'review', label: 'Review', subtypes: ['code_review', 'decision_review', 'function_review'] },
   { value: 'resolution', label: 'Resolution', subtypes: [] },
@@ -42,7 +42,7 @@ const makeInitialForm = (projectId = 0, milestoneId = 0): FormState => ({
   description: '',
   project_id: projectId,
   milestone_id: milestoneId,
-  task_type: 'task',
+  task_type: 'issue',  // P7.1: default changed from 'task' to 'issue'
   task_subtype: '',
   priority: 'medium',
   tags: '',

src/components/MilestoneFormModal.tsx

@@ -125,9 +125,9 @@ export default function MilestoneFormModal({ isOpen, onClose, onSaved, milestone
               Status
               <select value={form.status} onChange={(e) => setForm((f) => ({ ...f, status: e.target.value }))}>
                 <option value="open">Open</option>
-                <option value="pending">Pending</option>
-                <option value="deferred">Deferred</option>
-                <option value="progressing">Progressing</option>
+                <option value="freeze">Freeze</option>
+                <option value="undergoing">Undergoing</option>
+                <option value="completed">Completed</option>
                 <option value="closed">Closed</option>
               </select>
             </label>

src/components/Sidebar.tsx

@@ -32,6 +32,7 @@ export default function Sidebar({ user, onLogout }: Props) {
   const links = user ? [
     { to: '/', icon: '📊', label: 'Dashboard' },
     { to: '/projects', icon: '📁', label: 'Projects' },
+    { to: '/proposes', icon: '💡', label: 'Proposes' },
     { to: '/notifications', icon: '🔔', label: 'Notifications' + (unreadCount > 0 ? ' (' + unreadCount + ')' : '') },
     { to: '/monitor', icon: '📡', label: 'Monitor' },
     ...(user.is_admin ? [{ to: '/roles', icon: '🔐', label: 'Roles' }] : []),

src/index.css

@@ -72,6 +72,9 @@ tr.clickable:hover { background: var(--bg-hover); }
 .status-resolved { background: #10b981; }
 .status-closed { background: #6b7280; }
 .status-blocked { background: #ef4444; }
+.status-freeze { background: #8b5cf6; }
+.status-undergoing { background: #f59e0b; }
+.status-completed { background: #10b981; }
 .priority-low { background: #6b7280; }
 .priority-medium { background: #3b82f6; }
 .priority-high { background: #f59e0b; }

src/pages/CreateTaskPage.tsx

@@ -4,11 +4,11 @@ import api from '@/services/api'
 import type { Project, Milestone } from '@/types'
 
 const TASK_TYPES = [
-  { value: 'story', label: 'Story', subtypes: ['feature', 'improvement', 'refactor'] },
+  { value: 'story', label: 'Story', subtypes: ['improvement', 'refactor'] },  // P9.6: 'feature' removed — must come from propose accept
   { value: 'issue', label: 'Issue', subtypes: ['infrastructure', 'performance', 'regression', 'security', 'user_experience', 'defect'] },
-  { value: 'task', label: 'Task', subtypes: ['defect'] },
+  // P7.1: 'task' type removed — defect subtype migrated to issue/defect
   { value: 'test', label: 'Test', subtypes: ['regression', 'security', 'smoke', 'stress'] },
-  { value: 'maintenance', label: 'Maintenance', subtypes: ['deploy', 'release'] },
+  { value: 'maintenance', label: 'Maintenance', subtypes: ['deploy'] },  // P9.6: 'release' removed — controlled via milestone flow
   { value: 'research', label: 'Research', subtypes: [] },
   { value: 'review', label: 'Review', subtypes: ['code_review', 'decision_review', 'function_review'] },
   { value: 'resolution', label: 'Resolution', subtypes: [] },
@@ -19,7 +19,7 @@ export default function CreateTaskPage() {
   const [projects, setProjects] = useState<Project[]>([])
   const [milestones, setMilestones] = useState<Milestone[]>([])
   const [form, setForm] = useState({
-    title: '', description: '', project_id: 0, milestone_id: 0, task_type: 'task',
+    title: '', description: '', project_id: 0, milestone_id: 0, task_type: 'issue',  // P7.1: default changed from 'task' to 'issue'
     task_subtype: '', priority: 'medium', tags: '', reporter_id: 1,
   })
 

src/pages/MilestoneDetailPage.tsx

@@ -41,6 +41,11 @@ export default function MilestoneDetailPage() {
   const [newTitle, setNewTitle] = useState('')
   const [newDesc, setNewDesc] = useState('')
   const [projectCode, setProjectCode] = useState('')
+  const [actionLoading, setActionLoading] = useState<string | null>(null)
+  const [actionError, setActionError] = useState<string | null>(null)
+  const [showCloseConfirm, setShowCloseConfirm] = useState(false)
+  const [closeReason, setCloseReason] = useState('')
+  const [preflight, setPreflight] = useState<{ freeze?: { allowed: boolean; reason: string | null }; start?: { allowed: boolean; reason: string | null } } | null>(null)
 
   const fetchMilestone = () => {
     api.get<Milestone>(`/milestones/${id}`).then(({ data }) => {
@@ -51,11 +56,18 @@ export default function MilestoneDetailPage() {
           setProjectCode(proj.project_code || '')
         })
         api.get<ProjectMember[]>(`/projects/${data.project_id}/members`).then(({ data }) => setMembers(data)).catch(() => {})
+        fetchPreflight(data.project_id)
       }
     })
     api.get<MilestoneProgress>(`/milestones/${id}/progress`).then(({ data }) => setProgress(data)).catch(() => {})
   }
 
+  const fetchPreflight = (projectId: number) => {
+    api.get(`/projects/${projectId}/milestones/${id}/actions/preflight`)
+      .then(({ data }) => setPreflight(data))
+      .catch(() => setPreflight(null))
+  }
+
   useEffect(() => {
     fetchMilestone()
   }, [id])
@@ -96,7 +108,35 @@ export default function MilestoneDetailPage() {
     currentMemberRole === 'admin'
   ))
 
-  const isProgressing = milestone?.status === 'progressing'
+  const msStatus = milestone?.status
+  const isUndergoing = msStatus === 'undergoing'
+  const isTerminal = msStatus === 'completed' || msStatus === 'closed'
+
+  // --- Milestone action handlers (P8.2) ---
+  const performAction = async (action: string, body?: Record<string, unknown>) => {
+    if (!milestone || !project) return
+    setActionLoading(action)
+    setActionError(null)
+    try {
+      await api.post(`/projects/${project.id}/milestones/${milestone.id}/actions/${action}`, body ?? {})
+      fetchMilestone()
+      refreshMilestoneItems()
+      fetchPreflight(project.id)
+    } catch (err: any) {
+      const detail = err?.response?.data?.detail
+      setActionError(typeof detail === 'string' ? detail : `${action} failed`)
+    } finally {
+      setActionLoading(null)
+    }
+  }
+
+  const handleFreeze = () => performAction('freeze')
+  const handleStart = () => performAction('start')
+  const handleClose = () => {
+    performAction('close', closeReason ? { reason: closeReason } : {})
+    setShowCloseConfirm(false)
+    setCloseReason('')
+  }
 
   if (!milestone) return <div className="loading">Loading...</div>
 
@@ -117,11 +157,89 @@ export default function MilestoneDetailPage() {
       <div className="task-header">
         <h2>🏁 {milestone.title}</h2>
         <div className="task-meta">
-          <span className={`badge status-${milestone.status === 'progressing' ? 'in_progress' : milestone.status}`}>{milestone.status}</span>
+          <span className={`badge status-${milestone.status}`}>{milestone.status}</span>
           {milestone.due_date && <span className="text-dim">Due {dayjs(milestone.due_date).format('YYYY-MM-DD')}</span>}
           {milestone.planned_release_date && <span className="text-dim">Planned Release: {dayjs(milestone.planned_release_date).format('YYYY-MM-DD')}</span>}
+          {milestone.started_at && <span className="text-dim">Started: {dayjs(milestone.started_at).format('YYYY-MM-DD HH:mm')}</span>}
         </div>
-        {canEditMilestone && <button className="btn-transition" style={{ marginTop: 8 }} onClick={() => setShowEditMilestone(true)}>Edit Milestone</button>}
+        {canEditMilestone && msStatus === 'open' && <button className="btn-transition" style={{ marginTop: 8 }} onClick={() => setShowEditMilestone(true)}>Edit Milestone</button>}
+        {canEditMilestone && (msStatus === 'freeze' || msStatus === 'undergoing') && (
+          <span className="text-dim" style={{ marginTop: 8, display: 'inline-block' }}>
+            ⚠ Milestone is {msStatus} — scope fields are locked
+          </span>
+        )}
+
+        {/* Milestone status action buttons (P8.2) */}
+        {!isTerminal && (
+          <div style={{ display: 'flex', gap: 8, marginTop: 8, flexWrap: 'wrap', alignItems: 'center' }}>
+            {msStatus === 'open' && (
+              <span title={preflight?.freeze?.allowed === false ? preflight.freeze.reason ?? '' : ''}>
+                <button
+                  className="btn-primary"
+                  disabled={actionLoading === 'freeze' || preflight?.freeze?.allowed === false}
+                  onClick={handleFreeze}
+                  style={preflight?.freeze?.allowed === false ? { opacity: 0.5, cursor: 'not-allowed' } : {}}
+                >
+                  {actionLoading === 'freeze' ? '⏳ Freezing...' : '🧊 Freeze'}
+                </button>
+                {preflight?.freeze?.allowed === false && (
+                  <span className="text-dim" style={{ marginLeft: 8, fontSize: '0.85em' }}>
+                    ⚠ {preflight.freeze.reason}
+                  </span>
+                )}
+              </span>
+            )}
+            {msStatus === 'freeze' && (
+              <span title={preflight?.start?.allowed === false ? preflight.start.reason ?? '' : ''}>
+                <button
+                  className="btn-primary"
+                  disabled={actionLoading === 'start' || preflight?.start?.allowed === false}
+                  onClick={handleStart}
+                  style={preflight?.start?.allowed === false ? { opacity: 0.5, cursor: 'not-allowed' } : {}}
+                >
+                  {actionLoading === 'start' ? '⏳ Starting...' : '▶️ Start'}
+                </button>
+                {preflight?.start?.allowed === false && (
+                  <span className="text-dim" style={{ marginLeft: 8, fontSize: '0.85em' }}>
+                    ⚠ {preflight.start.reason}
+                  </span>
+                )}
+              </span>
+            )}
+            {(msStatus === 'open' || msStatus === 'freeze' || msStatus === 'undergoing') && (
+              <>
+                {!showCloseConfirm ? (
+                  <button
+                    className="btn-transition"
+                    style={{ color: 'var(--color-danger, #e74c3c)' }}
+                    onClick={() => setShowCloseConfirm(true)}
+                  >
+                    ✖ Close
+                  </button>
+                ) : (
+                  <div className="card" style={{ display: 'flex', gap: 8, alignItems: 'center', padding: '8px 12px' }}>
+                    <input
+                      placeholder="Reason (optional)"
+                      value={closeReason}
+                      onChange={(e) => setCloseReason(e.target.value)}
+                      style={{ minWidth: 180 }}
+                    />
+                    <button
+                      className="btn-primary"
+                      style={{ backgroundColor: 'var(--color-danger, #e74c3c)' }}
+                      disabled={actionLoading === 'close'}
+                      onClick={handleClose}
+                    >
+                      {actionLoading === 'close' ? 'Closing...' : 'Confirm Close'}
+                    </button>
+                    <button className="btn-back" onClick={() => { setShowCloseConfirm(false); setCloseReason('') }}>Cancel</button>
+                  </div>
+                )}
+              </>
+            )}
+          </div>
+        )}
+        {actionError && <p style={{ color: 'var(--color-danger, #e74c3c)', marginTop: 4 }}>⚠️ {actionError}</p>}
       </div>
 
       {milestone.description && (
@@ -154,14 +272,14 @@ export default function MilestoneDetailPage() {
 
       <div className="section">
         <div style={{ display: 'flex', gap: 8, marginBottom: 16 }}>
-          {!isProgressing && canEditMilestone && (
+          {!isTerminal && !isUndergoing && canEditMilestone && (
             <>
               <button className="btn-primary" onClick={() => { setActiveTab('tasks'); setShowCreateTask(true) }}>+ Create Task</button>
               <button className="btn-primary" onClick={() => { setActiveTab('supports'); setShowCreateSupport(true) }}>+ Create Support</button>
               <button className="btn-primary" onClick={() => { setActiveTab('meetings'); setShowCreateMeeting(true) }}>+ Schedule Meeting</button>
             </>
           )}
-          {isProgressing && <span className="text-dim">Milestone is in progress - cannot add new items</span>}
+          {(isUndergoing || isTerminal) && <span className="text-dim">{isTerminal ? `Milestone is ${msStatus}` : 'Milestone is undergoing'} — cannot add new items</span>}
         </div>
 
         <MilestoneFormModal

src/pages/MilestonesPage.tsx

@@ -51,7 +51,7 @@ export default function MilestonesPage() {
         {milestones.map((ms) => (
           <div key={ms.id} className="milestone-card" onClick={() => navigate(`/milestones/${ms.id}`)}>
             <div className="milestone-card-header">
-              <span className={`badge status-${ms.status === 'progressing' ? 'in_progress' : ms.status}`}>{ms.status}</span>
+              <span className={`badge status-${ms.status}`}>{ms.status}</span>
               <h3>{ms.title}</h3>
             </div>
             <p className="project-desc">{ms.description || 'No description'}</p>

src/pages/ProposeDetailPage.tsx

@@ -0,0 +1,265 @@
+import { useState, useEffect } from 'react'
+import { useParams, useNavigate, useSearchParams } from 'react-router-dom'
+import api from '@/services/api'
+import type { Propose, Milestone } from '@/types'
+import dayjs from 'dayjs'
+
+export default function ProposeDetailPage() {
+  const { id } = useParams()
+  const [searchParams] = useSearchParams()
+  const projectId = searchParams.get('project_id')
+  const navigate = useNavigate()
+
+  const [propose, setPropose] = useState<Propose | null>(null)
+  const [milestones, setMilestones] = useState<Milestone[]>([])
+  const [showAccept, setShowAccept] = useState(false)
+  const [selectedMilestone, setSelectedMilestone] = useState<number | ''>('')
+  const [actionLoading, setActionLoading] = useState(false)
+  const [error, setError] = useState('')
+
+  // Edit state (P10.7)
+  const [showEdit, setShowEdit] = useState(false)
+  const [editTitle, setEditTitle] = useState('')
+  const [editDescription, setEditDescription] = useState('')
+  const [editLoading, setEditLoading] = useState(false)
+
+  const fetchPropose = () => {
+    if (!projectId) return
+    api.get<Propose>(`/projects/${projectId}/proposes/${id}`).then(({ data }) => setPropose(data))
+  }
+
+  useEffect(() => {
+    fetchPropose()
+  }, [id, projectId])
+
+  const loadMilestones = () => {
+    if (!projectId) return
+    api.get<Milestone[]>(`/milestones?project_id=${projectId}`)
+      .then(({ data }) => setMilestones(data.filter((m) => m.status === 'open')))
+  }
+
+  const handleAccept = async () => {
+    if (!selectedMilestone || !projectId) return
+    setActionLoading(true)
+    setError('')
+    try {
+      await api.post(`/projects/${projectId}/proposes/${id}/accept`, { milestone_id: selectedMilestone })
+      setShowAccept(false)
+      fetchPropose()
+    } catch (err: any) {
+      setError(err.response?.data?.detail || 'Accept failed')
+    } finally {
+      setActionLoading(false)
+    }
+  }
+
+  const handleReject = async () => {
+    if (!projectId) return
+    const reason = prompt('Reject reason (optional):')
+    setActionLoading(true)
+    setError('')
+    try {
+      await api.post(`/projects/${projectId}/proposes/${id}/reject`, { reason: reason || undefined })
+      fetchPropose()
+    } catch (err: any) {
+      setError(err.response?.data?.detail || 'Reject failed')
+    } finally {
+      setActionLoading(false)
+    }
+  }
+
+  const openEditModal = () => {
+    if (!propose) return
+    setEditTitle(propose.title)
+    setEditDescription(propose.description || '')
+    setError('')
+    setShowEdit(true)
+  }
+
+  const handleEdit = async () => {
+    if (!projectId) return
+    setEditLoading(true)
+    setError('')
+    try {
+      await api.patch(`/projects/${projectId}/proposes/${id}`, {
+        title: editTitle,
+        description: editDescription,
+      })
+      setShowEdit(false)
+      fetchPropose()
+    } catch (err: any) {
+      setError(err.response?.data?.detail || 'Update failed')
+    } finally {
+      setEditLoading(false)
+    }
+  }
+
+  const handleReopen = async () => {
+    if (!projectId) return
+    setActionLoading(true)
+    setError('')
+    try {
+      await api.post(`/projects/${projectId}/proposes/${id}/reopen`)
+      fetchPropose()
+    } catch (err: any) {
+      setError(err.response?.data?.detail || 'Reopen failed')
+    } finally {
+      setActionLoading(false)
+    }
+  }
+
+  if (!propose) return <div className="loading">Loading...</div>
+
+  const statusBadgeClass = (s: string) => {
+    if (s === 'open') return 'status-open'
+    if (s === 'accepted') return 'status-completed'
+    if (s === 'rejected') return 'status-closed'
+    return ''
+  }
+
+  return (
+    <div className="task-detail">
+      <button className="btn-back" onClick={() => navigate(-1)}>← Back</button>
+
+      <div className="task-header">
+        <h2>
+          💡 {propose.title}
+          {propose.propose_code && <span className="badge" style={{ marginLeft: 8 }}>{propose.propose_code}</span>}
+        </h2>
+        <span className={`badge ${statusBadgeClass(propose.status)}`} style={{ fontSize: '1rem' }}>
+          {propose.status}
+        </span>
+      </div>
+
+      {error && <div className="error-message" style={{ color: 'var(--danger)', marginBottom: 12 }}>{error}</div>}
+
+      <div className="section">
+        <h3>Details</h3>
+        <div className="detail-grid">
+          <div><strong>Propose Code:</strong> {propose.propose_code || '—'}</div>
+          <div><strong>Status:</strong> {propose.status}</div>
+          <div><strong>Created By:</strong> User #{propose.created_by_id || '—'}</div>
+          <div><strong>Created:</strong> {dayjs(propose.created_at).format('YYYY-MM-DD HH:mm')}</div>
+          <div><strong>Updated:</strong> {propose.updated_at ? dayjs(propose.updated_at).format('YYYY-MM-DD HH:mm') : '—'}</div>
+          <div><strong>Feature Task:</strong> {propose.feat_task_id || '—'}</div>
+        </div>
+      </div>
+
+      <div className="section">
+        <h3>Description</h3>
+        <p style={{ whiteSpace: 'pre-wrap' }}>{propose.description || 'No description'}</p>
+      </div>
+
+      {/* Action buttons */}
+      <div className="section" style={{ display: 'flex', gap: 8, flexWrap: 'wrap' }}>
+        {propose.status === 'open' && (
+          <>
+            <button
+              className="btn-transition"
+              onClick={openEditModal}
+            >
+              ✏️ Edit
+            </button>
+            <button
+              className="btn-primary"
+              disabled={actionLoading}
+              onClick={() => { loadMilestones(); setShowAccept(true) }}
+            >
+              ✅ Accept
+            </button>
+            <button
+              className="btn-danger"
+              disabled={actionLoading}
+              onClick={handleReject}
+            >
+              ❌ Reject
+            </button>
+          </>
+        )}
+        {propose.status === 'accepted' && propose.feat_task_id && (
+          <button className="btn-transition" onClick={() => navigate(`/tasks/${propose.feat_task_id}`)}>
+            📋 View Generated Task
+          </button>
+        )}
+        {propose.status === 'rejected' && (
+          <button
+            className="btn-transition"
+            disabled={actionLoading}
+            onClick={handleReopen}
+          >
+            🔄 Reopen
+          </button>
+        )}
+      </div>
+
+      {/* Edit modal (P10.7 — only reachable when open) */}
+      {showEdit && (
+        <div className="modal-overlay" onClick={() => setShowEdit(false)}>
+          <div className="modal" onClick={(e) => e.stopPropagation()}>
+            <h3>Edit Propose</h3>
+            <label style={{ display: 'block', marginBottom: 8 }}>
+              <strong>Title</strong>
+              <input
+                type="text"
+                value={editTitle}
+                onChange={(e) => setEditTitle(e.target.value)}
+                style={{ width: '100%', marginTop: 4 }}
+              />
+            </label>
+            <label style={{ display: 'block', marginBottom: 8 }}>
+              <strong>Description</strong>
+              <textarea
+                value={editDescription}
+                onChange={(e) => setEditDescription(e.target.value)}
+                rows={6}
+                style={{ width: '100%', marginTop: 4 }}
+              />
+            </label>
+            <div style={{ marginTop: 12, display: 'flex', gap: 8 }}>
+              <button
+                className="btn-primary"
+                onClick={handleEdit}
+                disabled={!editTitle.trim() || editLoading}
+              >
+                {editLoading ? 'Saving...' : 'Save'}
+              </button>
+              <button className="btn-back" onClick={() => setShowEdit(false)}>Cancel</button>
+            </div>
+          </div>
+        </div>
+      )}
+
+      {/* Accept modal with milestone selector */}
+      {showAccept && (
+        <div className="modal-overlay" onClick={() => setShowAccept(false)}>
+          <div className="modal" onClick={(e) => e.stopPropagation()}>
+            <h3>Accept Propose</h3>
+            <p>Select an <strong>open</strong> milestone to create a feature story task in:</p>
+            <select
+              value={selectedMilestone}
+              onChange={(e) => setSelectedMilestone(Number(e.target.value))}
+            >
+              <option value="">— Select milestone —</option>
+              {milestones.map((ms) => (
+                <option key={ms.id} value={ms.id}>{ms.title}</option>
+              ))}
+            </select>
+            {milestones.length === 0 && (
+              <p style={{ color: 'var(--danger)', marginTop: 8 }}>No open milestones available.</p>
+            )}
+            <div style={{ marginTop: 12, display: 'flex', gap: 8 }}>
+              <button
+                className="btn-primary"
+                onClick={handleAccept}
+                disabled={!selectedMilestone || actionLoading}
+              >
+                {actionLoading ? 'Accepting...' : 'Confirm Accept'}
+              </button>
+              <button className="btn-back" onClick={() => setShowAccept(false)}>Cancel</button>
+            </div>
+          </div>
+        </div>
+      )}
+    </div>
+  )
+}

src/pages/ProposesPage.tsx

@@ -0,0 +1,110 @@
+import { useState, useEffect } from 'react'
+import { useNavigate } from 'react-router-dom'
+import api from '@/services/api'
+import type { Propose, Project } from '@/types'
+import dayjs from 'dayjs'
+
+export default function ProposesPage() {
+  const [proposes, setProposes] = useState<Propose[]>([])
+  const [projects, setProjects] = useState<Project[]>([])
+  const [projectFilter, setProjectFilter] = useState('')
+  const [showCreate, setShowCreate] = useState(false)
+  const [newTitle, setNewTitle] = useState('')
+  const [newDesc, setNewDesc] = useState('')
+  const [creating, setCreating] = useState(false)
+  const navigate = useNavigate()
+
+  const fetchProposes = () => {
+    if (!projectFilter) {
+      setProposes([])
+      return
+    }
+    api.get<Propose[]>(`/projects/${projectFilter}/proposes`).then(({ data }) => setProposes(data))
+  }
+
+  useEffect(() => {
+    api.get<Project[]>('/projects').then(({ data }) => setProjects(data))
+  }, [])
+
+  useEffect(() => { fetchProposes() }, [projectFilter])
+
+  const handleCreate = async () => {
+    if (!newTitle.trim() || !projectFilter) return
+    setCreating(true)
+    try {
+      await api.post(`/projects/${projectFilter}/proposes`, {
+        title: newTitle.trim(),
+        description: newDesc.trim() || null,
+      })
+      setNewTitle('')
+      setNewDesc('')
+      setShowCreate(false)
+      fetchProposes()
+    } finally {
+      setCreating(false)
+    }
+  }
+
+  const statusBadgeClass = (s: string) => {
+    if (s === 'open') return 'status-open'
+    if (s === 'accepted') return 'status-completed'
+    if (s === 'rejected') return 'status-closed'
+    return ''
+  }
+
+  return (
+    <div className="milestones-page">
+      <div className="page-header">
+        <h2>💡 Proposes ({proposes.length})</h2>
+        <button className="btn-primary" disabled={!projectFilter} onClick={() => setShowCreate(true)}>
+          + New Propose
+        </button>
+      </div>
+
+      <div className="filters">
+        <select value={projectFilter} onChange={(e) => setProjectFilter(e.target.value)}>
+          <option value="">Select a project</option>
+          {projects.map((p) => <option key={p.id} value={p.id}>{p.name}</option>)}
+        </select>
+      </div>
+
+      {!projectFilter && <p className="empty">Please select a project to view proposes.</p>}
+
+      <div className="milestone-grid">
+        {proposes.map((pr) => (
+          <div key={pr.id} className="milestone-card" onClick={() => navigate(`/proposes/${pr.id}?project_id=${pr.project_id}`)}>
+            <div className="milestone-card-header">
+              <span className={`badge ${statusBadgeClass(pr.status)}`}>{pr.status}</span>
+              {pr.propose_code && <span className="badge">{pr.propose_code}</span>}
+              <h3>{pr.title}</h3>
+            </div>
+            <p className="project-desc">{pr.description || 'No description'}</p>
+            <div className="project-meta">
+              {pr.feat_task_id && <span>Task: {pr.feat_task_id}</span>}
+              <span>Created {dayjs(pr.created_at).format('YYYY-MM-DD')}</span>
+            </div>
+          </div>
+        ))}
+        {projectFilter && proposes.length === 0 && <p className="empty">No proposes</p>}
+      </div>
+
+      {showCreate && (
+        <div className="modal-overlay" onClick={() => setShowCreate(false)}>
+          <div className="modal" onClick={(e) => e.stopPropagation()}>
+            <h3>New Propose</h3>
+            <label>Title</label>
+            <input value={newTitle} onChange={(e) => setNewTitle(e.target.value)} placeholder="Propose title" />
+            <label>Description</label>
+            <textarea value={newDesc} onChange={(e) => setNewDesc(e.target.value)} placeholder="Description (optional)" rows={4} />
+            <div style={{ marginTop: 12, display: 'flex', gap: 8 }}>
+              <button className="btn-primary" onClick={handleCreate} disabled={creating || !newTitle.trim()}>
+                {creating ? 'Creating...' : 'Create'}
+              </button>
+              <button className="btn-back" onClick={() => setShowCreate(false)}>Cancel</button>
+            </div>
+          </div>
+        </div>
+      )}
+    </div>
+  )
+}

src/pages/TaskDetailPage.tsx

@@ -17,6 +17,12 @@ export default function TaskDetailPage() {
   const [comments, setComments] = useState<Comment[]>([])
   const [newComment, setNewComment] = useState('')
   const [showEditTask, setShowEditTask] = useState(false)
+  const [actionLoading, setActionLoading] = useState<string | null>(null)
+  const [actionError, setActionError] = useState<string | null>(null)
+  const [showFinishModal, setShowFinishModal] = useState(false)
+  const [finishComment, setFinishComment] = useState('')
+  const [showCloseModal, setShowCloseModal] = useState(false)
+  const [closeReason, setCloseReason] = useState('')
 
   const refreshTask = async () => {
     const { data } = await api.get<Task>(`/tasks/${id}`)
@@ -43,31 +49,71 @@ export default function TaskDetailPage() {
     setComments(data)
   }
 
-  const transition = async (newStatus: string) => {
-    await api.post(`/tasks/${id}/transition?new_status=${newStatus}`)
+  const doAction = async (actionName: string, newStatus: string, body?: Record<string, any>) => {
+    setActionLoading(actionName)
+    setActionError(null)
+    try {
+      await api.post(`/tasks/${id}/transition?new_status=${newStatus}`, body || {})
       await refreshTask()
+      // refresh comments too (finish adds one via backend)
+      const { data } = await api.get<Comment[]>(`/tasks/${id}/comments`)
+      setComments(data)
+    } catch (err: any) {
+      setActionError(err?.response?.data?.detail || err?.message || 'Action failed')
+    } finally {
+      setActionLoading(null)
     }
+  }
+
+  const handleOpen = () => doAction('open', 'open')
+  const handleStart = () => doAction('start', 'undergoing')
+  const handleFinishConfirm = async () => {
+    if (!finishComment.trim()) return
+    await doAction('finish', 'completed', { comment: finishComment })
+    setShowFinishModal(false)
+    setFinishComment('')
+  }
+  const handleCloseConfirm = async () => {
+    const body: Record<string, any> = {}
+    if (closeReason.trim()) {
+      body.comment = `[Close reason] ${closeReason}`
+    }
+    await doAction('close', 'closed', body)
+    setShowCloseModal(false)
+    setCloseReason('')
+  }
+  const handleReopen = () => doAction('reopen', 'open')
 
   const currentMemberRole = useMemo(
     () => members.find((m) => m.user_id === user?.id)?.role,
     [members, user?.id]
   )
-  const canEditTask = Boolean(task && project && user && (
+  const isAdmin = Boolean(user && (
     user.is_admin ||
-    user.id === project.owner_id ||
-    user.id === task.created_by_id ||
-    user.id === milestone?.created_by_id ||
+    (project && user.id === project.owner_id) ||
     currentMemberRole === 'admin'
   ))
+  // P5.7/P9.3: assignee-aware edit permission
+  const canEditTask = Boolean(task && project && user && (() => {
+    const st = task.status
+    // undergoing/completed/closed: no body edits
+    if (st === 'undergoing' || st === 'completed' || st === 'closed') return false
+    // open + assignee set: only assignee or admin
+    if (st === 'open' && task.assignee_id != null) {
+      return user.id === task.assignee_id || isAdmin
+    }
+    // open + no assignee, or pending: general permission
+    return (
+      isAdmin ||
+      user.id === task.created_by_id ||
+      user.id === milestone?.created_by_id
+    )
+  })())
 
   if (!task) return <div className="loading">Loading...</div>
 
-  const statusActions: Record<string, string[]> = {
-    open: ['progressing', 'closed'],
-    pending: ['progressing', 'closed'],
-    progressing: ['pending', 'closed'],
-    closed: ['open'],
-  }
+  // Determine which action buttons to show based on status (P9.2 / P11.8)
+  const isTerminal = task.status === 'completed' || task.status === 'closed'
 
   return (
     <div className="task-detail">
@@ -81,7 +127,9 @@ export default function TaskDetailPage() {
           <span className="badge">{task.task_type}</span>{task.task_subtype && <span className="badge">{task.task_subtype}</span>}
           {task.tags && <span className="tags">{task.tags}</span>}
         </div>
-        {canEditTask && <button className="btn-transition" style={{ marginTop: 8 }} onClick={() => setShowEditTask(true)}>Edit Task</button>}
+        {canEditTask && (
+          <button className="btn-transition" style={{ marginTop: 8 }} onClick={() => setShowEditTask(true)}>Edit Task</button>
+        )}
       </div>
 
       <CreateTaskModal
@@ -108,14 +156,107 @@ export default function TaskDetailPage() {
         </div>
 
         <div className="section">
-          <h3>Status changes</h3>
-          <div className="actions">
-            {(statusActions[task.status] || []).map((s) => (
-              <button key={s} className="btn-transition" onClick={() => transition(s)}>{s}</button>
-            ))}
+          <h3>Actions</h3>
+          {actionError && <div className="error-message" style={{ color: '#dc2626', marginBottom: 8 }}>{actionError}</div>}
+          <div className="actions" style={{ display: 'flex', gap: 8, flexWrap: 'wrap' }}>
+            {/* pending: Open + Close */}
+            {task.status === 'pending' && (
+              <>
+                <button className="btn-transition" disabled={!!actionLoading} onClick={handleOpen}>
+                  {actionLoading === 'open' ? 'Opening…' : '▶ Open'}
+                </button>
+                <button className="btn-transition" style={{ background: '#dc2626', color: '#fff' }} disabled={!!actionLoading} onClick={() => setShowCloseModal(true)}>
+                  {actionLoading === 'close' ? 'Closing…' : '✕ Close'}
+                </button>
+              </>
+            )}
+            {/* open: Start + Close */}
+            {task.status === 'open' && (
+              <>
+                <button className="btn-transition" style={{ background: '#f59e0b', color: '#fff' }} disabled={!!actionLoading} onClick={handleStart}>
+                  {actionLoading === 'start' ? 'Starting…' : '⏵ Start'}
+                </button>
+                <button className="btn-transition" style={{ background: '#dc2626', color: '#fff' }} disabled={!!actionLoading} onClick={() => setShowCloseModal(true)}>
+                  {actionLoading === 'close' ? 'Closing…' : '✕ Close'}
+                </button>
+              </>
+            )}
+            {/* undergoing: Finish + Close */}
+            {task.status === 'undergoing' && (
+              <>
+                <button className="btn-transition" style={{ background: '#16a34a', color: '#fff' }} disabled={!!actionLoading} onClick={() => setShowFinishModal(true)}>
+                  {actionLoading === 'finish' ? 'Finishing…' : '✓ Finish'}
+                </button>
+                <button className="btn-transition" style={{ background: '#dc2626', color: '#fff' }} disabled={!!actionLoading} onClick={() => setShowCloseModal(true)}>
+                  {actionLoading === 'close' ? 'Closing…' : '✕ Close'}
+                </button>
+              </>
+            )}
+            {/* completed / closed: Reopen */}
+            {(task.status === 'completed' || task.status === 'closed') && (
+              <button className="btn-transition" disabled={!!actionLoading} onClick={handleReopen}>
+                {actionLoading === 'reopen' ? 'Reopening…' : '↺ Reopen'}
+              </button>
+            )}
           </div>
         </div>
 
+        {/* Finish modal — requires comment (P9.4) */}
+        {showFinishModal && (
+          <div className="modal-overlay" style={{ position: 'fixed', inset: 0, background: 'rgba(0,0,0,0.4)', display: 'flex', alignItems: 'center', justifyContent: 'center', zIndex: 1000 }}>
+            <div className="modal-content" style={{ background: '#fff', borderRadius: 8, padding: 24, minWidth: 400, maxWidth: 520 }}>
+              <h3>Finish Task</h3>
+              <p style={{ fontSize: 14, color: '#666', marginBottom: 12 }}>Please leave a completion comment before finishing.</p>
+              <textarea
+                value={finishComment}
+                onChange={(e) => setFinishComment(e.target.value)}
+                placeholder="Describe what was done…"
+                rows={4}
+                style={{ width: '100%', marginBottom: 12 }}
+              />
+              <div style={{ display: 'flex', gap: 8, justifyContent: 'flex-end' }}>
+                <button className="btn-transition" onClick={() => { setShowFinishModal(false); setFinishComment('') }}>Cancel</button>
+                <button
+                  className="btn-transition"
+                  style={{ background: '#16a34a', color: '#fff' }}
+                  disabled={!finishComment.trim() || !!actionLoading}
+                  onClick={handleFinishConfirm}
+                >
+                  {actionLoading === 'finish' ? 'Finishing…' : 'Confirm Finish'}
+                </button>
+              </div>
+            </div>
+          </div>
+        )}
+
+        {/* Close modal — optional reason */}
+        {showCloseModal && (
+          <div className="modal-overlay" style={{ position: 'fixed', inset: 0, background: 'rgba(0,0,0,0.4)', display: 'flex', alignItems: 'center', justifyContent: 'center', zIndex: 1000 }}>
+            <div className="modal-content" style={{ background: '#fff', borderRadius: 8, padding: 24, minWidth: 400, maxWidth: 520 }}>
+              <h3>Close Task</h3>
+              <p style={{ fontSize: 14, color: '#666', marginBottom: 12 }}>This will cancel/abandon the task. Optionally provide a reason.</p>
+              <textarea
+                value={closeReason}
+                onChange={(e) => setCloseReason(e.target.value)}
+                placeholder="Reason for closing (optional)…"
+                rows={3}
+                style={{ width: '100%', marginBottom: 12 }}
+              />
+              <div style={{ display: 'flex', gap: 8, justifyContent: 'flex-end' }}>
+                <button className="btn-transition" onClick={() => { setShowCloseModal(false); setCloseReason('') }}>Cancel</button>
+                <button
+                  className="btn-transition"
+                  style={{ background: '#dc2626', color: '#fff' }}
+                  disabled={!!actionLoading}
+                  onClick={handleCloseConfirm}
+                >
+                  {actionLoading === 'close' ? 'Closing…' : 'Confirm Close'}
+                </button>
+              </div>
+            </div>
+          </div>
+        )}
+
         <div className="section">
           <h3>Comments ({comments.length})</h3>
           {comments.map((c) => (

src/types/index.ts

@@ -33,9 +33,9 @@ export interface Task {
   id: number
   title: string
   description: string | null
-  task_type: 'issue' | 'maintenance' | 'research' | 'review' | 'story' | 'test' | 'resolution' | 'task'
+  task_type: 'issue' | 'maintenance' | 'research' | 'review' | 'story' | 'test' | 'resolution'  // P7.1: 'task' removed
   task_subtype: string | null
-  status: 'open' | 'pending' | 'progressing' | 'closed'
+  status: 'open' | 'pending' | 'undergoing' | 'completed' | 'closed'
   priority: 'low' | 'medium' | 'high' | 'critical'
   project_id: number
   milestone_id: number | null
@@ -64,7 +64,8 @@ export interface Milestone {
   id: number
   title: string
   description: string | null
-  status: 'open' | 'pending' | 'deferred' | 'progressing' | 'closed'
+  status: 'open' | 'freeze' | 'undergoing' | 'completed' | 'closed'
+  started_at: string | null
   project_id: number
   created_by_id: number | null
   due_date: string | null
@@ -119,6 +120,19 @@ export interface DashboardStats {
   recent_tasks: Task[]
 }
 
+export interface Propose {
+  id: number
+  propose_code: string | null
+  title: string
+  description: string | null
+  status: 'open' | 'accepted' | 'rejected'
+  project_id: number
+  created_by_id: number | null
+  feat_task_id: string | null
+  created_at: string
+  updated_at: string | null
+}
+
 export interface LoginResponse {
   access_token: string
   token_type: string