feat(mobile,deploy): 接入安卓极光与华为通道并准备公网部署配置

客户端默认指向 jxd.jinniu.ink 的 HTTPS/WSS；登录后把 OpenIM userID 设为极光 alias。
华为 agconnect-services.json 不伪造、不入库。Master Secret 只从服务器文件注入。

Co-authored-by: multica-agent <github@multica.ai>

mobile/lib/main.dart

@@ -7,10 +7,12 @@ import 'screens/home_screen.dart';
 import 'screens/login_screen.dart';
 import 'services/call_service.dart';
 import 'services/im_service.dart';
+import 'services/push_service.dart';
 import 'theme.dart';
 
 void main() {
   WidgetsFlutterBinding.ensureInitialized();
+  PushService.instance.init();
   runApp(const ChanglianApp());
 }
 
@@ -27,6 +29,7 @@ class _ChanglianAppState extends State<ChanglianApp> {
     super.initState();
     // 被踢下线 / token 失效：清凭证、回登录页
     IMService.instance.onForceLogout = () async {
+      await PushService.instance.unbindUser();
       await LoginScreen.clearCredential();
       navigatorKey.currentState?.pushAndRemoveUntil(
         MaterialPageRoute(builder: (_) => const LoginScreen()),
@@ -90,6 +93,7 @@ class _SplashGateState extends State<SplashGate> {
       await im.init().timeout(const Duration(seconds: 20));
       await im.login(userID: credential.$1, token: credential.$2).timeout(const Duration(seconds: 20));
       CallService.instance.start();
+      await PushService.instance.bindUser(credential.$1);
       if (!mounted) return;
       Navigator.of(context).pushReplacement(MaterialPageRoute(builder: (_) => const HomeScreen()));
       return;