feat: 添加起卦教程首次访问追踪和Agent时间上下文

- 后端 ProfileSettingsV1 添加 DivinationTutorialSettings 字段
- 前端三个起卦页面添加首次访问检测，自动弹出教程
- 教程展示后更新 settings 标记，避免重复弹出
- 使用本地状态管理避免并发更新覆盖问题
- Agent 系统提示添加时间上下文信息

apps/lib/features/settings/data/models/profile_settings.dart

@@ -59,6 +59,31 @@ class NotificationSettings {
   }
 }
 
+class DivinationTutorialSettings {
+  const DivinationTutorialSettings({
+    this.divinationEntryShown = true,
+    this.autoDivinationShown = true,
+    this.manualDivinationShown = true,
+  });
+
+  final bool divinationEntryShown;
+  final bool autoDivinationShown;
+  final bool manualDivinationShown;
+
+  DivinationTutorialSettings copyWith({
+    bool? divinationEntryShown,
+    bool? autoDivinationShown,
+    bool? manualDivinationShown,
+  }) {
+    return DivinationTutorialSettings(
+      divinationEntryShown: divinationEntryShown ?? this.divinationEntryShown,
+      autoDivinationShown: autoDivinationShown ?? this.autoDivinationShown,
+      manualDivinationShown:
+          manualDivinationShown ?? this.manualDivinationShown,
+    );
+  }
+}
+
 class ProfileSettingsV1 {
   const ProfileSettingsV1({
     this.version = 1,
@@ -69,6 +94,7 @@ class ProfileSettingsV1 {
     this.preferences = const PreferenceSettings(),
     this.privacy = const <String, Object?>{},
     this.notification = const NotificationSettings(),
+    this.divinationTutorial = const DivinationTutorialSettings(),
   });
 
   final int version;
@@ -79,6 +105,7 @@ class ProfileSettingsV1 {
   final PreferenceSettings preferences;
   final Map<String, Object?> privacy;
   final NotificationSettings notification;
+  final DivinationTutorialSettings divinationTutorial;
 
   ProfileSettingsV1 copyWith({
     int? version,
@@ -89,6 +116,7 @@ class ProfileSettingsV1 {
     PreferenceSettings? preferences,
     Map<String, Object?>? privacy,
     NotificationSettings? notification,
+    DivinationTutorialSettings? divinationTutorial,
   }) {
     return ProfileSettingsV1(
       version: version ?? this.version,
@@ -99,6 +127,7 @@ class ProfileSettingsV1 {
       preferences: preferences ?? this.preferences,
       privacy: privacy ?? this.privacy,
       notification: notification ?? this.notification,
+      divinationTutorial: divinationTutorial ?? this.divinationTutorial,
     );
   }