fix: delete agent 500 error + dynamic personality + deployment guide

- Fix delete agent 500: clean up FK records (agent_llm_logs, permissions,
  schedules, executions, team_members) and unbind goals/tasks before delete
- Remove hardcoded personality templates in Android, replace with dynamic
  system prompt generation from name + description
- Set promptSectionsEnabled=false to bypass PromptComposer for personality
- Add Tencent Cloud Linux deployment guide (Docker Compose)
- Accumulated backend service updates, frontend UI fixes, Android app changes

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/api/tasks.py

@@ -1,5 +1,7 @@
 """
-Task API — 任务管理接口
+Task API — 任务管理接口 (含原子认领 + 依赖图 + Agent 状态)
+
+参考 Claude Code src/utils/tasks.ts 的 API 设计
 """
 from fastapi import APIRouter, Depends, Query
 from sqlalchemy.orm import Session
@@ -9,6 +11,7 @@ from datetime import datetime
 import logging
 
 from app.core.database import get_db
+from app.core.task_system import TaskSystem, ClaimResult, AgentState, AgentStatus
 from app.api.auth import get_current_user
 from app.models.user import User
 from app.services import goal_service
@@ -92,6 +95,42 @@ class TaskDependencyCheck(BaseModel):
     pending_dependencies: List[str] = []
 
 
+class ClaimTaskRequest(BaseModel):
+    agent_id: str = Field(..., description="认领任务的 Agent 标识")
+    check_busy: bool = Field(default=True, description="是否检查 Agent 忙碌状态")
+
+
+class ClaimTaskResponse(BaseModel):
+    success: bool
+    reason: Optional[str] = None
+    task: Optional[TaskResponse] = None
+    busy_with_tasks: List[str] = []
+    blocked_by_tasks: List[str] = []
+
+
+class BlockTaskRequest(BaseModel):
+    from_task_id: str = Field(..., description="阻塞方任务ID")
+    to_task_id: str = Field(..., description="被阻塞方任务ID")
+
+
+class AgentStatusResponse(BaseModel):
+    agent_id: str
+    status: str  # idle / busy
+    current_tasks: List[str] = []
+
+
+class ReleaseTaskRequest(BaseModel):
+    agent_id: str = Field(..., description="释放任务的 Agent 标识")
+
+
+class TaskCompleteRequest(BaseModel):
+    result: Optional[Dict[str, Any]] = None
+
+
+class TaskFailRequest(BaseModel):
+    error_message: str = ""
+
+
 # ──────────────────────────── Endpoints ────────────────────────────
 
 @router.post("", response_model=TaskResponse, status_code=201)
@@ -307,3 +346,160 @@ async def retry_task(
             error_message=str(e),
         )
     return goal_service.get_task(db, task_id)
+
+
+# ════════════════════ 任务系统增强 (参考 Claude Code task_system) ════════════════════
+
+
+def _get_task_system(db: Session) -> TaskSystem:
+    return TaskSystem(db)
+
+
+@router.post("/{task_id}/claim", response_model=ClaimTaskResponse)
+def claim_task(
+    task_id: str,
+    data: ClaimTaskRequest,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """原子认领任务 (SELECT FOR UPDATE)，检查依赖+Agent忙碌"""
+    ts = _get_task_system(db)
+    result = ts.claim_task(task_id=task_id, agent_id=data.agent_id, check_busy=data.check_busy)
+    return ClaimTaskResponse(
+        success=result.success,
+        reason=result.reason,
+        task=TaskResponse.model_validate(result.task) if result.task else None,
+        busy_with_tasks=result.busy_with_tasks,
+        blocked_by_tasks=result.blocked_by_tasks,
+    )
+
+
+@router.post("/block", status_code=200)
+def block_task(
+    data: BlockTaskRequest,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """设置任务依赖: from_task 阻塞 to_task"""
+    ts = _get_task_system(db)
+    ok = ts.block_task(data.from_task_id, data.to_task_id)
+    if not ok:
+        from fastapi import HTTPException
+        raise HTTPException(404, "任务不存在")
+    return {"message": "ok", "from": data.from_task_id, "to": data.to_task_id}
+
+
+@router.delete("/block", status_code=200)
+def unblock_task(
+    data: BlockTaskRequest,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """移除任务依赖"""
+    ts = _get_task_system(db)
+    ok = ts.unblock_task(data.from_task_id, data.to_task_id)
+    if not ok:
+        from fastapi import HTTPException
+        raise HTTPException(404, "任务不存在")
+    return {"message": "ok"}
+
+
+@router.get("/agent/{agent_id}/status", response_model=AgentStatusResponse)
+def get_agent_status(
+    agent_id: str,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """获取 Agent 忙闲状态 (idle/busy)"""
+    ts = _get_task_system(db)
+    state = ts.get_agent_status(agent_id)
+    return AgentStatusResponse(
+        agent_id=state.agent_id,
+        status=state.status.value,
+        current_tasks=state.current_tasks,
+    )
+
+
+@router.post("/{task_id}/release", status_code=200)
+def release_task(
+    task_id: str,
+    data: ReleaseTaskRequest,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """Agent 主动释放单个任务"""
+    ts = _get_task_system(db)
+    ok = ts.release_task(task_id, data.agent_id)
+    if not ok:
+        from fastapi import HTTPException
+        raise HTTPException(404, "任务不存在或不属于该 Agent")
+    return {"message": "ok", "task_id": task_id}
+
+
+@router.post("/agent/{agent_id}/unassign", status_code=200)
+def unassign_agent_tasks(
+    agent_id: str,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """释放 Agent 所有未完成任务 (Agent 下线时调用)"""
+    ts = _get_task_system(db)
+    tasks = ts.unassign_agent_tasks(agent_id)
+    return {"message": "ok", "unassigned_count": len(tasks), "task_ids": [t.id for t in tasks]}
+
+
+@router.post("/{task_id}/complete", response_model=TaskResponse)
+def complete_task(
+    task_id: str,
+    data: TaskCompleteRequest = TaskCompleteRequest(),
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """标记任务完成 (自动检查被阻塞任务)"""
+    ts = _get_task_system(db)
+    task = ts.complete_task(task_id, result=data.result)
+    if not task:
+        from fastapi import HTTPException
+        raise HTTPException(404, "任务不存在")
+    return TaskResponse.model_validate(task)
+
+
+@router.post("/{task_id}/fail", response_model=TaskResponse)
+def fail_task(
+    task_id: str,
+    data: TaskFailRequest = TaskFailRequest(),
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """标记任务失败"""
+    ts = _get_task_system(db)
+    task = ts.fail_task(task_id, error_message=data.error_message)
+    if not task:
+        from fastapi import HTTPException
+        raise HTTPException(404, "任务不存在")
+    return TaskResponse.model_validate(task)
+
+
+@router.get("/available/{goal_id}", response_model=List[TaskResponse])
+def get_available_tasks(
+    goal_id: str,
+    limit: int = Query(default=10, ge=1, le=100),
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """获取目标下所有可执行任务 (依赖满足 + 未被认领)"""
+    ts = _get_task_system(db)
+    tasks = ts.get_next_available_tasks(goal_id, limit=limit)
+    return [TaskResponse.model_validate(t) for t in tasks]
+
+
+@router.get("/{task_id}/blockers", response_model=List[TaskResponse])
+def get_task_blockers(
+    task_id: str,
+    current_user: User = Depends(get_current_user),
+    db: Session = Depends(get_db),
+):
+    """获取任务尚未完成的阻塞依赖"""
+    ts = _get_task_system(db)
+    blockers = ts.get_unresolved_blockers(task_id)
+    return [TaskResponse.model_validate(t) for t in blockers]