feat: enhance settings view and feature defaults management

- Introduced default feature model settings in the settings view, allowing users to specify the default AI model for new feature cards.
- Updated navigation to include a direct link to model defaults in the settings menu.
- Enhanced the Add Feature dialog to utilize the default feature model from the app store.
- Implemented synchronization of the default feature model in settings migration and sync hooks.
- Improved UI components to reflect changes in default settings, ensuring a cohesive user experience.

apps/ui/src/routes/settings.tsx

@@ -1,6 +1,16 @@
 import { createFileRoute } from '@tanstack/react-router';
 import { SettingsView } from '@/components/views/settings-view';
+import type { SettingsViewId } from '@/components/views/settings-view/hooks';
+
+interface SettingsSearchParams {
+  view?: SettingsViewId;
+}
 
 export const Route = createFileRoute('/settings')({
   component: SettingsView,
+  validateSearch: (search: Record<string, unknown>): SettingsSearchParams => {
+    return {
+      view: search.view as SettingsViewId | undefined,
+    };
+  },
 });