Add FCM push notifications, queue alerts, caller ID fixes, and auto-revert agent status

Server-side:
- Add push credential auto-creation for FCM incoming call notifications
- Add queue alert FCM notifications (data-only for background delivery)
- Add queue alert cancellation on call accept/disconnect
- Fix caller ID to show caller's number instead of Twilio number
- Fix FCM token storage when refresh_token is null
- Add pre_call_status tracking to revert agent status 30s after call ends
- Add SSE fallback polling for mobile app connectivity

Mobile app:
- Add Android telecom permissions and phone account registration
- Add VoiceFirebaseMessagingService for incoming call push handling
- Add insistent queue alert notifications with custom sound
- Fix caller number display on active call screen
- Add caller ID selection dropdown on dashboard
- Add phone numbers endpoint and provider support
- Add unit tests for CallInfo, QueueState, and CallProvider
- Remove local.properties from tracking, add .gitignore

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

mobile/lib/services/auth_service.dart

@@ -1,4 +1,6 @@
 import 'dart:async';
+import 'dart:convert';
+import 'package:dio/dio.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import '../models/user.dart';
 import 'api_client.dart';
@@ -14,11 +16,15 @@ class AuthService {
       {String? fcmToken}) async {
     await _api.setBaseUrl(serverUrl);
 
-    final response = await _api.dio.post('/auth/login', data: {
-      'username': username,
-      'password': password,
-      if (fcmToken != null) 'fcm_token': fcmToken,
-    });
+    final response = await _api.dio.post(
+      '/auth/login',
+      data: {
+        'username': username,
+        'password': password,
+        if (fcmToken != null) 'fcm_token': fcmToken,
+      },
+      options: Options(receiveTimeout: const Duration(seconds: 60)),
+    );
 
     final data = response.data;
     if (data['success'] != true) {
@@ -27,24 +33,31 @@ class AuthService {
 
     await _storage.write(key: 'access_token', value: data['access_token']);
     await _storage.write(key: 'refresh_token', value: data['refresh_token']);
+    await _storage.write(key: 'user_data', value: jsonEncode(data['user']));
 
     _scheduleRefresh(data['expires_in'] as int? ?? 3600);
 
     return User.fromJson(data['user']);
   }
 
-  Future<bool> tryRestoreSession() async {
+  Future<User?> tryRestoreSession() async {
     final token = await _storage.read(key: 'access_token');
-    if (token == null) return false;
+    if (token == null) return null;
 
     await _api.restoreBaseUrl();
-    if (_api.dio.options.baseUrl.isEmpty) return false;
+    if (_api.dio.options.baseUrl.isEmpty) return null;
 
     try {
       final response = await _api.dio.get('/agent/status');
-      return response.statusCode == 200;
+      if (response.statusCode != 200) return null;
+
+      final userData = await _storage.read(key: 'user_data');
+      if (userData != null) {
+        return User.fromJson(jsonDecode(userData) as Map<String, dynamic>);
+      }
+      return null;
     } catch (_) {
-      return false;
+      return null;
     }
   }