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/pages/auth/login_page.dart

@@ -1,5 +1,8 @@
+import 'dart:io' show Platform;
+
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:sign_in_with_apple/sign_in_with_apple.dart';
 import '../../core/app_colors.dart';
 import '../../core/navigation_provider.dart';
 import '../../providers/auth_provider.dart';
@@ -63,6 +66,70 @@ class _LoginPageState extends ConsumerState<LoginPage> {
     }
   }
 
+  // Apple 登录
+  Future<void> _appleSignIn() async {
+    if (_loading) return;
+    setState(() {
+      _loading = true;
+      _error = null;
+      _successMsg = null;
+    });
+
+    try {
+      final credential = await SignInWithApple.getAppleIDCredential(
+        scopes: [
+          AppleIDAuthorizationScopes.fullName,
+        ],
+        webAuthenticationOptions: WebAuthenticationOptions(
+          clientId: 'com.datalumina.YYA.signin',
+          redirectUri: Uri.parse(
+            'https://erpapi.datalumina.cn/xiaomai/api/auth/apple-login',
+          ),
+        ),
+      );
+
+      final identityToken = credential.identityToken;
+      if (identityToken == null) {
+        if (mounted) {
+          setState(() {
+            _loading = false;
+            _error = 'Apple 登录未返回身份信息，请重试';
+          });
+        }
+        return;
+      }
+
+      final name = credential.givenName != null && credential.familyName != null
+          ? '${credential.familyName}${credential.givenName}'
+          : null;
+
+      final err = await ref.read(authProvider.notifier).appleLogin(
+            identityToken,
+            credential.authorizationCode,
+            name,
+          );
+      if (mounted) {
+        setState(() => _loading = false);
+        if (err != null) {
+          setState(() => _error = err);
+        } else {
+          _goHome();
+        }
+      }
+    } catch (e) {
+      if (mounted) {
+        setState(() {
+          _loading = false;
+          if (e is SignInWithAppleAuthorizationException) {
+            _error = 'Apple 登录已取消';
+          } else {
+            _error = 'Apple 登录失败: $e';
+          }
+        });
+      }
+    }
+  }
+
   Future<void> _submit() async {
     if (!_agreed) {
       final accepted = await _showAgreementDialog();
@@ -489,6 +556,15 @@ class _LoginPageState extends ConsumerState<LoginPage> {
                                     label: _isLogin ? '登录' : '注册',
                                     onTap: _loading ? null : _submit,
                                   ),
+                                  // Apple 登录按钮（仅 iOS/macOS）
+                                  if (_isLogin && (Platform.isIOS || Platform.isMacOS)) ...[
+                                    const SizedBox(height: 20),
+                                    SignInWithAppleButton(
+                                      onPressed: _loading ? () {} : () { _appleSignIn(); },
+                                      style: SignInWithAppleButtonStyle.whiteOutlined,
+                                      height: 48,
+                                    ),
+                                  ],
                                   const SizedBox(height: 16),
                                   GestureDetector(
                                     onTap: () => setState(() {