fix(platform): remove auto-fix identity selection and fix feed loading race condition

- Remove problematic $ensureActiveIdentityPopulated() that auto-selected identities
- Add user-friendly $needsActiveIdentitySelection() and $getAvailableAccountDids() methods
- Fix missing updateActiveDid implementation in CapacitorPlatformService
- Resolve race condition in HomeView initialization causing feed loading failures
- Improve TypeScript error handling in ContactsView invite processing

Addresses team concerns about data consistency and user control for identity selection.

src/services/platforms/CapacitorPlatformService.ts

@@ -1319,6 +1319,13 @@ export class CapacitorPlatformService implements PlatformService {
     await this.dbExec(sql, params);
   }
 
+  async updateActiveDid(did: string): Promise<void> {
+    await this.dbExec(
+      "UPDATE active_identity SET activeDid = ?, lastUpdated = datetime('now') WHERE id = 1",
+      [did],
+    );
+  }
+
   async insertNewDidIntoSettings(did: string): Promise<void> {
     await this.dbExec("INSERT INTO settings (accountDid) VALUES (?)", [did]);
   }