feat: initial frontend - React + TypeScript + Vite

- Login page with JWT auth
- Dashboard with stats and charts
- Issues list with pagination, filtering
- Issue detail with comments, status transitions
- Create issue form
- Dark theme UI
- Docker (nginx) with API proxy to backend
- Sidebar navigation

src/pages/CreateIssuePage.tsx

@@ -0,0 +1,60 @@
+import { useState, useEffect } from 'react'
+import { useNavigate } from 'react-router-dom'
+import api from '@/services/api'
+import type { Project } from '@/types'
+
+export default function CreateIssuePage() {
+  const navigate = useNavigate()
+  const [projects, setProjects] = useState<Project[]>([])
+  const [form, setForm] = useState({
+    title: '', description: '', project_id: 0, issue_type: 'task',
+    priority: 'medium', tags: '', reporter_id: 1,
+  })
+
+  useEffect(() => {
+    api.get<Project[]>('/projects').then(({ data }) => {
+      setProjects(data)
+      if (data.length) setForm((f) => ({ ...f, project_id: data[0].id }))
+    })
+  }, [])
+
+  const submit = async (e: React.FormEvent) => {
+    e.preventDefault()
+    const payload = { ...form, tags: form.tags || null }
+    await api.post('/issues', payload)
+    navigate('/issues')
+  }
+
+  return (
+    <div className="create-issue">
+      <h2>新建 Issue</h2>
+      <form onSubmit={submit}>
+        <label>标题 <input required value={form.title} onChange={(e) => setForm({ ...form, title: e.target.value })} /></label>
+        <label>描述 <textarea value={form.description} onChange={(e) => setForm({ ...form, description: e.target.value })} /></label>
+        <label>项目
+          <select value={form.project_id} onChange={(e) => setForm({ ...form, project_id: Number(e.target.value) })}>
+            {projects.map((p) => <option key={p.id} value={p.id}>{p.name}</option>)}
+          </select>
+        </label>
+        <label>类型
+          <select value={form.issue_type} onChange={(e) => setForm({ ...form, issue_type: e.target.value })}>
+            <option value="task">Task</option>
+            <option value="bug">Bug</option>
+            <option value="feature">Feature</option>
+            <option value="resolution">Resolution</option>
+          </select>
+        </label>
+        <label>优先级
+          <select value={form.priority} onChange={(e) => setForm({ ...form, priority: e.target.value })}>
+            <option value="low">Low</option>
+            <option value="medium">Medium</option>
+            <option value="high">High</option>
+            <option value="critical">Critical</option>
+          </select>
+        </label>
+        <label>标签 <input value={form.tags} onChange={(e) => setForm({ ...form, tags: e.target.value })} placeholder="逗号分隔" /></label>
+        <button type="submit" className="btn-primary">创建</button>
+      </form>
+    </div>
+  )
+}