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

.trellis/tasks/04-15-divination-tutorial-first-visit/task.json

@@ -0,0 +1,44 @@
+{
+  "id": "divination-tutorial-first-visit",
+  "name": "divination-tutorial-first-visit",
+  "title": "divination-tutorial-first-visit",
+  "description": "",
+  "status": "planning",
+  "dev_type": null,
+  "scope": null,
+  "priority": "P2",
+  "creator": "zl-q",
+  "assignee": "zl-q",
+  "createdAt": "2026-04-15",
+  "completedAt": null,
+  "branch": null,
+  "base_branch": "dev",
+  "worktree_path": null,
+  "current_phase": 0,
+  "next_action": [
+    {
+      "phase": 1,
+      "action": "implement"
+    },
+    {
+      "phase": 2,
+      "action": "check"
+    },
+    {
+      "phase": 3,
+      "action": "finish"
+    },
+    {
+      "phase": 4,
+      "action": "create-pr"
+    }
+  ],
+  "commit": null,
+  "pr_url": null,
+  "subtasks": [],
+  "children": [],
+  "parent": null,
+  "relatedFiles": [],
+  "notes": "",
+  "meta": {}
+}