feat: 集成 Apple Sign-In + iOS 上线准备

- 后端新增 Apple 登录端点 /api/auth/apple-login
- 新增 AppleTokenValidator 验证 IdentityToken
- User 实体添加 AppleUserId 字段，Phone 改为可空
- 前端添加 sign_in_with_apple 依赖和 Apple 登录按钮
- 统一 Bundle ID 为 com.datalumina.YYA，显示名称为小脉健康
- 配置 DEVELOPMENT_TEAM 和 Sign in with Apple Entitlements
- 补充 NSCamera/NSPhotoLibrary 权限描述
- 生产 API 地址改为 https://erpapi.datalumina.cn/xiaomai
- Flutter 升级至 3.44.6 / Dart 3.12.2

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

health_app/lib/providers/auth_provider.dart

@@ -207,6 +207,40 @@ class AuthNotifier extends Notifier<AuthState> {
     }
   }
 
+  /// Apple 登录
+  Future<String?> appleLogin(String identityToken, String? authorizationCode, String? name) async {
+    try {
+      final api = ref.read(apiClientProvider);
+      final response = await api.post(
+        '/api/auth/apple-login',
+        data: {
+          'identityToken': identityToken,
+          if (authorizationCode != null) 'authorizationCode': authorizationCode,
+          if (name != null && name.isNotEmpty) 'name': name,
+        },
+      );
+      final data = response.data['data'];
+      if (data == null) return response.data['message'] ?? 'Apple 登录失败';
+
+      await api.saveTokens(data['accessToken'], data['refreshToken']);
+      final user = data['user'];
+      state = AuthState(
+        isLoggedIn: true,
+        isLoading: false,
+        user: UserInfo(
+          id: user['id'] ?? '',
+          phone: user['phone'] ?? '',
+          role: user['role'] ?? 'User',
+          name: user['name'],
+          avatarUrl: user['avatarUrl'],
+        ),
+      );
+      return null;
+    } catch (e) {
+      return 'Apple 登录失败: $e';
+    }
+  }
+
   /// 登出
   Future<void> logout() async {
     final api = ref.read(apiClientProvider);