feat: 添加视觉设计语言系统并重构认证页面UI

- 新增 visual_design_language.md 设计规范文档
- 新增 auth 设计 tokens (authBackground, authCard, authInput, feedback 系列等)
- 重构登录/注册/验证码/重置密码页面为新设计系统
- 新增 AuthHeroHeader, AuthSurfaceCard, AuthSection, AuthField, PasswordField 组件
- 重构 AppBanner 和 Toast 支持多类型配置 (info/success/warning/error)
- 后端 AgentScope: 重整 schemas/prompts/tools 作用域, 新增协议文档
- 更新 AGENTS.md 集成视觉设计语言约束

apps/lib/core/startup/auth_session_bootstrapper.dart

@@ -0,0 +1,38 @@
+import '../../features/auth/presentation/bloc/auth_state.dart';
+import '../../features/calendar/data/services/calendar_service.dart';
+import '../notifications/local_notification_service.dart';
+
+class AuthSessionBootstrapper {
+  AuthSessionBootstrapper({
+    required CalendarService calendarService,
+    required LocalNotificationService notificationService,
+  }) : _calendarService = calendarService,
+       _notificationService = notificationService;
+
+  final CalendarService _calendarService;
+  final LocalNotificationService _notificationService;
+
+  String? _syncedUserId;
+
+  Future<void> syncForAuthState(AuthState state) async {
+    if (state is! AuthAuthenticated) {
+      _syncedUserId = null;
+      return;
+    }
+
+    if (_syncedUserId == state.user.id) {
+      return;
+    }
+
+    _syncedUserId = state.user.id;
+
+    try {
+      final now = DateTime.now();
+      final end = now.add(const Duration(days: 90));
+      final events = await _calendarService.getEventsForRange(now, end);
+      await _notificationService.rebuildUpcomingReminders(events);
+    } catch (_) {
+      // ignore reminder bootstrap failures
+    }
+  }
+}