Enhance AppShell and Sidebar components with new navigation for components

Updated the AppShell component to include new pages for models, knowledge, and tools under the components section. Refactored the Sidebar to introduce a dedicated section for these components, improving navigation structure and user experience. Added new placeholder pages for ComponentsModelsPage, ComponentsKnowledgePage, and ComponentsToolsPage, each with relevant titles and descriptions.

src/components/pages/ComponentsModelsPage.tsx

@@ -0,0 +1,11 @@
+import { PlaceholderPage } from "./PlaceholderPage";
+
+export function ComponentsModelsPage() {
+  return (
+    <PlaceholderPage
+      label="资源管理"
+      title="模型资源"
+      description="统一管理大语言模型、语音识别、声音资源、知识库与工具插件。"
+    />
+  );
+}