feat: align iOS client safety and consent experience

health_app/lib/pages/settings/ai_consent_details_page.dart

@@ -32,7 +32,15 @@ class AiConsentDetailsPage extends ConsumerWidget {
     );
     if (confirmed != true || !context.mounted) return;
 
-    await ref.read(aiConsentProvider.notifier).revoke(userId);
+    final revoked = await ref.read(aiConsentProvider.notifier).revoke(userId);
+    if (!revoked) {
+      if (context.mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          const SnackBar(content: Text('Authorization could not be revoked.')),
+        );
+      }
+      return;
+    }
     await ref.read(authProvider.notifier).logout();
   }
 
@@ -59,6 +67,7 @@ class AiConsentDetailsPage extends ConsumerWidget {
             color: AppColors.textPrimary,
           ),
         ),
+        centerTitle: true,
       ),
       body: SafeArea(
         child: SingleChildScrollView(
@@ -91,8 +100,11 @@ class AiConsentDetailsPage extends ConsumerWidget {
                 SizedBox(
                   width: double.infinity,
                   child: OutlinedButton(
-                    onPressed: () => _revoke(context, ref),
+                    onPressed: consent.isSaving
+                        ? null
+                        : () => _revoke(context, ref),
                     style: OutlinedButton.styleFrom(
+                      backgroundColor: Colors.white,
                       foregroundColor: AppColors.error,
                       side: BorderSide(
                         color: AppColors.error.withValues(alpha: 0.4),

health_app/lib/pages/settings/settings_pages.dart

@@ -1,4 +1,3 @@
-import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:shadcn_ui/shadcn_ui.dart';
@@ -56,13 +55,11 @@ class SettingsPage extends ConsumerWidget {
                       title: '长辈模式',
                       onTap: () => pushRoute(ref, 'elderMode'),
                     ),
-                    if (!Platform.isIOS)
-                      // iOS 审核版：蓝牙设备入口已移除
-                      _SettingsTile(
-                        icon: LucideIcons.bell,
-                        title: '消息通知',
-                        onTap: () => pushRoute(ref, 'notificationPrefs'),
-                      ),
+                    _SettingsTile(
+                      icon: LucideIcons.bell,
+                      title: '消息通知',
+                      onTap: () => pushRoute(ref, 'notificationPrefs'),
+                    ),
                     _SettingsTile(
                       icon: LucideIcons.info,
                       title: '关于小脉健康',