feat(web): 插件管理弹窗（启停 / 重载）

- 顶栏新增「插件管理」图标按钮，打开 PluginsDialog
- 弹窗列出 pugins/ 下的插件：标题 / 目录名 / 是否启用与已加载 / 平台 label / 能力清单
- 每个插件可启用、停用、重载，底部有「全部重载」
- 启停成功后重新拉 /api/platforms，「添加账号」的平台下拉同步刷新
- types.ts 新增 PluginInfo；App.tsx 把平台列表加载提成 loadPlatforms 复用
- static/ 重新构建（pnpm typecheck + pnpm build 均通过）
- 顺带把 .vscode/ 纳入跟踪

web/src/App.tsx

@@ -3,6 +3,7 @@ import { Plus, RefreshCw, Users, WifiOff } from 'lucide-react'
 
 import { AccountCard } from './components/AccountCard'
 import { AddAccountDialog, type NewAccount } from './components/AddAccountDialog'
+import { PluginsDialog } from './components/PluginsDialog'
 import { QuizDialog } from './components/QuizDialog'
 import { SettingsDialog } from './components/SettingsDialog'
 import { StatBar } from './components/StatBar'
@@ -48,6 +49,7 @@ interface InlineLog {
 type DialogState =
   | { type: 'add' }
   | { type: 'settings' }
+  | { type: 'plugins' }
   | { type: 'system' }
   | { type: 'quiz'; accountId: string; course: Course }
   | null
@@ -194,19 +196,23 @@ export default function App() {
     return () => window.clearInterval(timer)
   }, [load])
 
-  useEffect(() => {
-    api<{ platforms: PlatformInfo[] }>('/api/platforms')
-      .then((response) => {
-        const list = response.platforms || []
-        if (!list.length) return
-        setPlatformList(list)
-        const map: Record<string, string> = {}
-        for (const platform of list) map[platform.id] = platform.label
-        setPlatforms(map)
-      })
-      .catch(() => {})
+  const loadPlatforms = useCallback(async () => {
+    try {
+      const response = await api<{ platforms: PlatformInfo[] }>('/api/platforms')
+      const list = response.platforms || []
+      setPlatformList(list)
+      const map: Record<string, string> = {}
+      for (const platform of list) map[platform.id] = platform.label
+      setPlatforms(map)
+    } catch {
+      // 后端未连接时保留上一次的平台列表
+    }
   }, [])
 
+  useEffect(() => {
+    void loadPlatforms()
+  }, [loadPlatforms])
+
   const pullLog = useCallback(
     async (id: string) => {
       const current = logsRef.current[id] || {
@@ -656,6 +662,7 @@ export default function App() {
         onRefresh={() => void refreshNow()}
         onSettings={() => setDialog({ type: 'settings' })}
         onSystemLog={() => setDialog({ type: 'system' })}
+        onPlugins={() => setDialog({ type: 'plugins' })}
         onAdd={() => setDialog({ type: 'add' })}
       />
 
@@ -773,6 +780,12 @@ export default function App() {
         notify={notify}
       />
       <SystemLogDialog open={dialog?.type === 'system'} onClose={() => setDialog(null)} />
+      <PluginsDialog
+        open={dialog?.type === 'plugins'}
+        onClose={() => setDialog(null)}
+        notify={notify}
+        onChanged={() => void loadPlatforms()}
+      />
       <QuizDialog
         open={dialog?.type === 'quiz' && !!quizAccount}
         account={quizAccount}