feat: remove nginx, add projects/milestones/notifications pages

- Dockerfile: replace nginx with serve for static files
- Fix auth endpoint: /auth/login → /auth/token
- Add ProjectsPage, ProjectDetailPage
- Add MilestonesPage, MilestoneDetailPage with progress bar
- Add NotificationsPage with unread count
- Sidebar: add milestones/notifications nav, live unread badge
- API: configurable VITE_API_BASE for host nginx proxy
- Types: add Milestone, MilestoneProgress, Notification, ProjectMember

src/pages/ProjectsPage.tsx

@@ -0,0 +1,64 @@
+import { useState, useEffect } from 'react'
+import { useNavigate } from 'react-router-dom'
+import api from '@/services/api'
+import type { Project } from '@/types'
+import dayjs from 'dayjs'
+
+export default function ProjectsPage() {
+  const [projects, setProjects] = useState<Project[]>([])
+  const [showCreate, setShowCreate] = useState(false)
+  const [form, setForm] = useState({ name: '', description: '', owner_id: 1 })
+  const navigate = useNavigate()
+
+  const fetchProjects = () => {
+    api.get<Project[]>('/projects').then(({ data }) => setProjects(data))
+  }
+
+  useEffect(() => { fetchProjects() }, [])
+
+  const createProject = async (e: React.FormEvent) => {
+    e.preventDefault()
+    await api.post('/projects', form)
+    setForm({ name: '', description: '', owner_id: 1 })
+    setShowCreate(false)
+    fetchProjects()
+  }
+
+  return (
+    <div className="projects-page">
+      <div className="page-header">
+        <h2>📁 项目 ({projects.length})</h2>
+        <button className="btn-primary" onClick={() => setShowCreate(!showCreate)}>
+          {showCreate ? '取消' : '+ 新建项目'}
+        </button>
+      </div>
+
+      {showCreate && (
+        <form className="inline-form" onSubmit={createProject}>
+          <input
+            required placeholder="项目名称" value={form.name}
+            onChange={(e) => setForm({ ...form, name: e.target.value })}
+          />
+          <input
+            placeholder="项目描述（可选）" value={form.description}
+            onChange={(e) => setForm({ ...form, description: e.target.value })}
+          />
+          <button type="submit" className="btn-primary">创建</button>
+        </form>
+      )}
+
+      <div className="project-grid">
+        {projects.map((p) => (
+          <div key={p.id} className="project-card" onClick={() => navigate(`/projects/${p.id}`)}>
+            <h3>{p.name}</h3>
+            <p className="project-desc">{p.description || '暂无描述'}</p>
+            <div className="project-meta">
+              <span>创建于 {dayjs(p.created_at).format('YYYY-MM-DD')}</span>
+            </div>
+          </div>
+        ))}
+        {projects.length === 0 && <p className="empty">暂无项目，点击上方创建</p>}
+      </div>
+    </div>
+  )
+}