feat(web): Day 9 — Web ChatPage + 会话 API 前端

- ChatPage 组件: 左侧会话列表(260px) + 右侧聊天区 + RichMessage 富消息
- 新建/选择/重命名/关闭会话，session_id 模式消息持久化
- aiChatApi 新增 createSession/listSessions/renameSession/closeSession
- 路由 /ai/chat 注册，支持 display_hints 富消息渲染
- App.tsx 路由权限校验覆盖

apps/web/src/App.tsx

@@ -47,6 +47,7 @@ const AiAnalysisList = lazy(() => import('./pages/health/AiAnalysisList'));
 const AiUsageDashboard = lazy(() => import('./pages/health/AiUsageDashboard'));
 const AiConfigPage = lazy(() => import('./pages/health/AiConfigPage'));
 const AiKnowledgePage = lazy(() => import('./pages/health/AiKnowledgePage'));
+const AiChatPage = lazy(() => import('./pages/ai/ChatPage'));
 const AlertList = lazy(() => import('./pages/health/AlertList'));
 const AlertDashboard = lazy(() => import('./pages/health/AlertDashboard'));
 const AlertRuleList = lazy(() => import('./pages/health/AlertRuleList'));
@@ -257,6 +258,7 @@ export default function App() {
       "/health/points-rules", "/health/points-products", "/health/points-orders",
       "/health/offline-events", "/health/ai-prompts", "/health/ai-analysis",
       "/health/ai-usage", "/health/ai-config", "/health/ai-knowledge", "/health/alerts", "/health/alert-dashboard",
+      "/ai/chat",
       "/health/alert-rules", "/health/devices", "/health/realtime-monitor",
       "/health/oauth-clients", "/health/dialysis", "/health/action-inbox",
       "/health/follow-up-templates", "/health/care-plans", "/health/shifts",
@@ -329,6 +331,7 @@ export default function App() {
                       <Route path="/health/ai-usage" element={<AiUsageDashboard />} />
                       <Route path="/health/ai-config" element={<AiConfigPage />} />
                       <Route path="/health/ai-knowledge" element={<AiKnowledgePage />} />
+                      <Route path="/ai/chat" element={<AiChatPage />} />
                       <Route path="/health/alerts" element={<AlertList />} />
                       <Route path="/health/alert-dashboard" element={<AlertDashboard />} />
                       <Route path="/health/alert-rules" element={<AlertRuleList />} />