feat(task): 添加任务修订功能和超时处理机制

添加了 `revise_task` 路由动作类型，允许用户修改、纠正或重新执行最新活动任务结果。
实现了工具失败指导原则，防止相同类别工具重复失败。
为任务规划器添加了超时处理机制，避免长时间等待。

BREAKING CHANGE: 任务路由逻辑已更新，新增 `revise_task` 动作类型。

fix(api): 修复任务详情API返回完整流程投影

修复了任务详情API端点，现在会包含过滤后的流程运行、事件和工件信息，
并确保时间戳字段正确序列化。

refactor(engine): 优化任务技能解析器摘要节点处理

改进了任务技能解析器对摘要节点的处理逻辑，对于仅依赖文本生成功能的摘要节
点不再分配具体技能，直接使用依赖项输出进行汇总。

test: 增加任务修订和超时处理测试用例

添加了测试用例验证任务修订输入记录反馈、超时回退到单模式以及
摘要节点技能解析等新功能。

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

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import asyncio
 import json
 from dataclasses import dataclass, field
 from typing import Any, Literal
@@ -77,6 +78,7 @@ class TaskExecutionPlanner:
         attempt_index: int,
         latest_validation: ValidationResult | None = None,
         provider_bundle: ProviderBundle | None = None,
+        timeout_seconds: float = 30.0,
     ) -> TaskExecutionPlan:
         provider = None
         model = None
@@ -87,29 +89,32 @@ class TaskExecutionPlanner:
         if provider is None:
             return TaskExecutionPlan.single("planner_provider_unavailable")
         try:
-            response = await provider.chat(
-                messages=[
-                    {
-                        "role": "system",
-                        "content": (
-                            "You choose whether an internal Beaver Task attempt should run as a single "
-                            "main-agent pass or use a small sub-agent team first. Return only compact JSON."
-                        ),
-                    },
-                    {
-                        "role": "user",
-                        "content": self._prompt(
-                            task=task,
-                            user_message=user_message,
-                            attempt_index=attempt_index,
-                            latest_validation=latest_validation,
-                        ),
-                    },
-                ],
-                tools=None,
-                model=model,
-                max_tokens=4096,
-                temperature=0.0,
+            response = await asyncio.wait_for(
+                provider.chat(
+                    messages=[
+                        {
+                            "role": "system",
+                            "content": (
+                                "You choose whether an internal Beaver Task attempt should run as a single "
+                                "main-agent pass or use a small sub-agent team first. Return only compact JSON."
+                            ),
+                        },
+                        {
+                            "role": "user",
+                            "content": self._prompt(
+                                task=task,
+                                user_message=user_message,
+                                attempt_index=attempt_index,
+                                latest_validation=latest_validation,
+                            ),
+                        },
+                    ],
+                    tools=None,
+                    model=model,
+                    max_tokens=4096,
+                    temperature=0.0,
+                ),
+                timeout=timeout_seconds,
             )
             plan = self.from_json(response.content or "")
             return await self._resolve_plan(
@@ -120,7 +125,9 @@ class TaskExecutionPlanner:
                 provider_bundle=provider_bundle,
             )
         except Exception as exc:
-            return TaskExecutionPlan.single("planner_failed", fallback_error=str(exc))
+            detail = str(exc)
+            error = f"{type(exc).__name__}: {detail}" if detail else type(exc).__name__
+            return TaskExecutionPlan.single("planner_failed", fallback_error=error)
 
     async def _resolve_plan(
         self,