Add monitor section placeholders for history and dashboard pages.

Wire dashboard navigation in AppShell and fix the 监控观察 sidebar group highlight so it activates for history and dashboard routes.

Co-authored-by: Cursor <cursoragent@cursor.com>

src/components/layout/AppShell.tsx

@@ -10,6 +10,7 @@ import { ComponentsModelsPage } from "@/components/pages/ComponentsModelsPage";
 import { ComponentsKnowledgePage } from "@/components/pages/ComponentsKnowledgePage";
 import { ComponentsToolsPage } from "@/components/pages/ComponentsToolsPage";
 import { HistoryPage } from "@/components/pages/HistoryPage";
+import { DashboardPage } from "@/components/pages/DashboardPage";
 import { TestPage } from "@/components/pages/TestPage";
 import { WorkflowPage } from "@/components/pages/WorkflowPage";
 import { ProfilePage } from "@/components/pages/ProfilePage";
@@ -21,6 +22,7 @@ export type NavKey =
   | "components-knowledge"
   | "components-tools"
   | "history"
+  | "dashboard"
   | "test"
   | "workflow"
   | "profile";
@@ -49,6 +51,7 @@ export function AppShell() {
           {active === "components-knowledge" && <ComponentsKnowledgePage />}
           {active === "components-tools" && <ComponentsToolsPage />}
           {active === "history" && <HistoryPage />}
+          {active === "dashboard" && <DashboardPage />}
           {active === "test" && <TestPage />}
           {active === "workflow" && <WorkflowPage />}
           {active === "profile" && <ProfilePage />}