feat(analytics): add optional Aptabase event tracking UI

Integrate Aptabase analytics via a Tauri plugin and add a privacy
notice flow plus a settings dialog to control whether anonymous
usage events are sent. The app now tracks key user actions while
ensuring analytics never blocks core Git operations.

- Add analytics tracking helper and Aptabase plugin wiring
- Persist analytics consent in localStorage and gate tracking
- Introduce notice and settings dialogs, plus new event calls

src/lib/types.ts

@@ -33,6 +33,11 @@ export interface AiSettings {
   customModel: string;
 }
 
+export interface AnalyticsSettings {
+  enabled: boolean;
+  noticeSeen: boolean;
+}
+
 export interface GitStatus {
   repo_path: string;
   current_branch: string | null;