feat(client): 实时授权状态与会话失效处理

- 心跳读取 /auth/ping 回带的授权概况，直接刷新横幅/状态栏/只读门禁，省去单独轮询 /license/info
- 账号被停用/删除（401 USER_DISABLED）即强制重新登录
- 令牌持久化经串行队列 + 会话代号守卫，杜绝续期写入与登出交叉把失效 token 写回
- 写操作门禁（write_guard）+ 授权文案（license_copy）按 grace/readonly/locked 分阶段降级

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/lib/screens/settings/settings_screen.dart

@@ -12,19 +12,21 @@ import '../../core/auth/auth_state.dart';
 import '../../widgets/write_guard.dart';
 import '../../core/config/app_config.dart';
 import '../../core/config/app_info.dart';
+import '../../core/config/license_copy.dart';
 import '../../core/responsive/responsive.dart';
 import '../../core/theme/app_theme.dart';
 import '../../models/number_rule.dart';
 import '../../models/user.dart';
 import '../../providers/license_provider.dart';
-import '../../repositories/license_repository.dart';
 import '../../providers/number_rule_provider.dart';
 import '../../providers/user_provider.dart';
 import '../../providers/shop_provider.dart';
 import '../../models/shop.dart';
 
 class SettingsScreen extends ConsumerStatefulWidget {
-  const SettingsScreen({super.key});
+  /// 初始选中的 Tab（0=酒行信息 … 4=授权 … 5=数据管理）。
+  final int initialTab;
+  const SettingsScreen({super.key, this.initialTab = 0});
 
   @override
   ConsumerState<SettingsScreen> createState() => _SettingsScreenState();
@@ -44,6 +46,7 @@ class _SettingsScreenState extends ConsumerState<SettingsScreen> {
   Widget build(BuildContext context) {
     return DefaultTabController(
       length: 6,
+      initialIndex: widget.initialTab,
       child: Column(
         children: [
           Container(
@@ -276,17 +279,21 @@ class _SettingsScreenState extends ConsumerState<SettingsScreen> {
                             children: WriteGuard.isReadonly(ref)
                                 ? const []
                                 : [
-                              TextButton(
-                                onPressed: () =>
-                                    _showEditUserDialog(context, u),
-                                child: const Text('编辑',
-                                    style: TextStyle(fontSize: 12)),
+                              WriteGuard(
+                                child: TextButton(
+                                  onPressed: () =>
+                                      _showEditUserDialog(context, u),
+                                  child: const Text('编辑',
+                                      style: TextStyle(fontSize: 12)),
+                                ),
                               ),
-                              TextButton(
-                                onPressed: () =>
-                                    _showResetPasswordDialog(context, u),
-                                child: const Text('重置密码',
-                                    style: TextStyle(fontSize: 12)),
+                              WriteGuard(
+                                child: TextButton(
+                                  onPressed: () =>
+                                      _showResetPasswordDialog(context, u),
+                                  child: const Text('重置密码',
+                                      style: TextStyle(fontSize: 12)),
+                                ),
                               ),
                             ],
                           )),
@@ -326,6 +333,9 @@ class _SettingsScreenState extends ConsumerState<SettingsScreen> {
             ),
           ),
           const SizedBox(height: 16),
+          // 过期降级说明
+          _buildExpiryNotes(),
+          const SizedBox(height: 16),
           // 激活码输入区
           _buildActivationCard(),
         ],
@@ -349,24 +359,8 @@ class _SettingsScreenState extends ConsumerState<SettingsScreen> {
       );
     }
 
-    Color phaseColor;
-    String phaseText;
-    switch (lic.phase) {
-      case 'grace':
-        phaseColor = Colors.orange;
-        phaseText = '宽限期（剩余 ${lic.daysRemaining ?? 0} 天到期）';
-      case 'readonly':
-        phaseColor = AppTheme.danger;
-        phaseText = '已过期 · 只读模式';
-      case 'locked':
-        phaseColor = AppTheme.danger;
-        phaseText = '已锁定 · 请立即续费';
-      default:
-        phaseColor = AppTheme.success;
-        phaseText = lic.expiresAt == null
-            ? '正常（永久授权）'
-            : '正常（剩余 ${lic.daysRemaining ?? 0} 天）';
-    }
+    final Color phaseColor = LicenseCopy.phaseColor(lic.phase);
+    final String phaseText = LicenseCopy.statusText(lic);
 
     return Column(
       crossAxisAlignment: CrossAxisAlignment.start,
@@ -407,6 +401,53 @@ class _SettingsScreenState extends ConsumerState<SettingsScreen> {
     );
   }
 
+  Widget _buildExpiryNotes() {
+    return Card(
+      child: Padding(
+        padding: const EdgeInsets.all(20),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            Row(
+              children: const [
+                Icon(Icons.info_outline,
+                    size: 16, color: AppTheme.textSecondary),
+                SizedBox(width: 6),
+                Text('过期说明',
+                    style:
+                        TextStyle(fontSize: 14, fontWeight: FontWeight.w600)),
+              ],
+            ),
+            const SizedBox(height: 4),
+            const Text('授权到期后会分阶段降级，请在到期前及时续费',
+                style:
+                    TextStyle(fontSize: 13, color: AppTheme.textSecondary)),
+            const SizedBox(height: 12),
+            for (final note in LicenseCopy.degradationNotes())
+              Padding(
+                padding: const EdgeInsets.symmetric(vertical: 4),
+                child: Row(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    const Padding(
+                      padding: EdgeInsets.only(top: 6, right: 8),
+                      child: Icon(Icons.circle,
+                          size: 5, color: AppTheme.textSecondary),
+                    ),
+                    Expanded(
+                      child: Text(note,
+                          style: const TextStyle(
+                              fontSize: 13, height: 1.5)),
+                    ),
+                  ],
+                ),
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+
   Widget _buildActivationCard() {
     return Card(
       child: Padding(
@@ -789,6 +830,19 @@ class _SettingsScreenState extends ConsumerState<SettingsScreen> {
             style: TextStyle(color: AppTheme.textSecondary)),
       );
     }
+    if (WriteGuard.licenseBlocked(ref)) {
+      final lic = ref.watch(licenseProvider).valueOrNull;
+      return Center(
+        child: Padding(
+          padding: const EdgeInsets.all(24),
+          child: Text(
+            lic == null ? '授权已过期，暂时无法导入' : LicenseCopy.writeBlockedToast(lic),
+            textAlign: TextAlign.center,
+            style: const TextStyle(color: AppTheme.textSecondary),
+          ),
+        ),
+      );
+    }
     final currentUser = ref.watch(authStateProvider).user;
     final isSuperAdmin = currentUser?.role == 'superadmin';
     return _BatchImportWidget(isSuperAdmin: isSuperAdmin);