Fix duplicate export declarations and migrate ContactsView with sub-components

- Remove duplicate NOTIFY_INVITE_MISSING and NOTIFY_INVITE_PROCESSING_ERROR exports
- Update InviteOneAcceptView.vue to use correct NOTIFY_INVITE_TRUNCATED_DATA constant
- Migrate ContactsView to PlatformServiceMixin and extract into modular sub-components
- Resolves TypeScript compilation errors preventing web build

src/services/platforms/CapacitorPlatformService.ts

@@ -1302,5 +1302,7 @@ export class CapacitorPlatformService implements PlatformService {
 
   // --- PWA/Web-only methods (no-op for Capacitor) ---
   public registerServiceWorker(): void {}
-  public get isPWAEnabled(): boolean { return false; }
+  public get isPWAEnabled(): boolean {
+    return false;
+  }
 }