feat(engine): 添加MCP连接管理和工具集成功能

- 集成MCP连接管理器，支持MCP服务器连接
- 添加多种内置工具：ClarifyTool、CronTool、DelegateTool、ExecuteCodeTool、
  PatchFileTool、ProcessTool、SendMessageTool、SpawnTool、TerminalTool、
  TodoTool、WebFetchTool、WebSearchTool、WriteFileTool等
- 实现工具注册和装配功能
- 添加技能选择上下文参数
- 支持思考模式控制参数thinking_enabled

feat(coordinator): 重构任务执行计划器参数命名

- 将learning_candidate_enabled重命名为allow_candidate_generation
- 更新TeamGraphScheduler中的参数传递
- 修改LocalAgentRunner中的相关参数处理
- 更新README文档中的相应描述

refactor(context): 标准化工具调用参数格式

- 添加_json导入用于参数序列化
- 实现_provider_tool_calls方法标准化OpenAI兼容的工具调用载荷
- 修复工具调用中参数非字符串类型的序列化问题

refactor(session): 优化消息历史记录过滤逻辑

- 修改get_messages_as_conversation为基于运行状态过滤消息
- 排除未完成、失败或错误结束的运行记录
- 改进对话历史的可见性控制机制

fix(store): 修复FTS索引重建逻辑

- 添加异常处理防止FTS索引创建失败
- 实现_rebuild_fts_index方法重新构建全文搜索索引
- 优化索引触发器和表的维护流程

app-instance/backend/beaver/tasks/service.py

@@ -24,6 +24,8 @@ class TaskService:
         metadata: dict[str, Any] | None = None,
     ) -> TaskRecord:
         now = self._now()
+        task_metadata = dict(metadata or {})
+        task_metadata.setdefault("short_title", short_task_title(description))
         task = TaskRecord(
             task_id=uuid4().hex,
             session_id=session_id,
@@ -35,7 +37,7 @@ class TaskService:
             creator=creator,
             created_at=now,
             updated_at=now,
-            metadata=dict(metadata or {}),
+            metadata=task_metadata,
         )
         self.store.upsert_task(task)
         self._event(task, "created", payload={"description": description})
@@ -44,11 +46,45 @@ class TaskService:
     def get_task(self, task_id: str) -> TaskRecord | None:
         return self.store.get_task(task_id)
 
+    def list_tasks(self) -> list[TaskRecord]:
+        return sorted(self.store.list_tasks(), key=lambda item: item.updated_at, reverse=True)
+
+    def list_events(self, task_id: str) -> list[TaskEvent]:
+        return self.store.list_events(task_id=task_id)
+
     def get_task_by_run_id(self, run_id: str) -> TaskRecord | None:
         return self.store.get_task_by_run_id(run_id)
 
-    def get_latest_open_task(self, session_id: str) -> TaskRecord | None:
-        return self.store.get_latest_open_task(session_id)
+    def get_latest_open_task(self, session_id: str, *, include_unengaged_scheduled: bool = False) -> TaskRecord | None:
+        tasks = [
+            task
+            for task in self.store.list_tasks()
+            if task.session_id == session_id and task.is_open
+        ]
+        if not include_unengaged_scheduled:
+            tasks = [task for task in tasks if self._is_user_visible_active_task(task)]
+        if not tasks:
+            return None
+        return sorted(tasks, key=lambda item: item.updated_at)[-1]
+
+    def active_task_view(self, session_id: str) -> dict[str, Any] | None:
+        task = self.get_latest_open_task(session_id)
+        if task is None:
+            return None
+        return self.to_api_dict(task)
+
+    def to_api_dict(self, task: TaskRecord) -> dict[str, Any]:
+        payload = task.to_dict()
+        payload["short_title"] = self.ensure_short_title(task).metadata.get("short_title")
+        payload["is_open"] = task.is_open
+        return payload
+
+    def ensure_short_title(self, task: TaskRecord) -> TaskRecord:
+        if task.metadata.get("short_title"):
+            return task
+        task.metadata["short_title"] = short_task_title(task.description or task.goal or task.task_id)
+        self.store.upsert_task(task)
+        return task
 
     def start_run(self, task_id: str, *, user_message: str, attempt_index: int) -> TaskRecord:
         task = self._require(task_id)
@@ -136,6 +172,38 @@ class TaskService:
         self._event(task, f"feedback_{feedback_type}", run_id=run_id, payload=entry)
         return task
 
+    def close_task(self, task_id: str, *, reason: str = "closed") -> TaskRecord:
+        task = self._require(task_id)
+        now = self._now()
+        task.status = "closed"
+        task.closed_at = now
+        task.close_reason = reason
+        task.updated_at = now
+        self.store.upsert_task(task)
+        self._event(task, "closed", payload={"reason": reason})
+        return task
+
+    def abandon_task(self, task_id: str, *, reason: str = "abandoned") -> TaskRecord:
+        task = self._require(task_id)
+        now = self._now()
+        task.status = "abandoned"
+        task.closed_at = now
+        task.close_reason = reason
+        task.updated_at = now
+        self.store.upsert_task(task)
+        self._event(task, "abandoned", payload={"reason": reason})
+        return task
+
+    def delete_task(self, task_id: str) -> bool:
+        return self.store.delete_task(task_id)
+
+    @staticmethod
+    def _is_user_visible_active_task(task: TaskRecord) -> bool:
+        if task.creator != "cron":
+            return True
+        metadata = task.metadata or {}
+        return bool(metadata.get("user_engaged") or metadata.get("requires_followup"))
+
     def _require(self, task_id: str) -> TaskRecord:
         task = self.store.get_task(task_id)
         if task is None:
@@ -165,3 +233,15 @@ class TaskService:
     @staticmethod
     def _now() -> str:
         return datetime.now(timezone.utc).isoformat()
+
+
+def short_task_title(text: str) -> str:
+    cleaned = " ".join((text or "").strip().split())
+    if not cleaned:
+        return "当前任务"
+    if any("\u4e00" <= char <= "\u9fff" for char in cleaned):
+        return cleaned[:15]
+    words = cleaned.split()
+    if len(words) <= 4:
+        return cleaned[:40]
+    return " ".join(words[:4])[:40]