feat: diagnose_project 运行中任务返回 claimed_by+心跳陈旧度，agent 可直接识别僵尸任务

pipeline_service/agent_loop_v2.py

@@ -856,6 +856,31 @@ class AgentExecutor:
             for sr in (submitted_rows or []):
                 lines.append(f"  - [{getattr(sr, 'role', '?')}] {getattr(sr, 'title', '')} (id={getattr(sr, 'id', '')})")
 
+        # 运行中任务明细：claimed_by + 心跳陈旧度，帮助 agent 直接识别僵尸任务
+        # （进程崩溃/协程挂起后心跳不再更新，超时即疑似僵尸，会被 poller 自动回收重跑）
+        if rc:
+            running_rows = await sor.sqlExe(
+                "SELECT id, title, role, claimed_by, "
+                "TIMESTAMPDIFF(MINUTE, updated_at, NOW()) AS mins "
+                "FROM pipeline_tasks WHERE tenant_id=${pid}$ AND state='running' "
+                "ORDER BY updated_at ASC LIMIT 10",
+                {"pid": pid})
+            lines.append("运行中任务:")
+            for rr in (running_rows or []):
+                rrole = getattr(rr, 'role', '?')
+                rtitle = getattr(rr, 'title', '')
+                rid = getattr(rr, 'id', '')
+                rcb = getattr(rr, 'claimed_by', '') or ''
+                try:
+                    mins = int(getattr(rr, 'mins', 0) or 0)
+                except (TypeError, ValueError):
+                    mins = 0
+                if mins >= 10:
+                    flag = f"⚠️心跳超时{mins}分钟(疑似僵尸,将被回收重跑)"
+                else:
+                    flag = f"已运行{mins}分钟"
+                lines.append(f"  - [{rrole}] {rtitle} (id={rid}) | {flag} | claimed_by={rcb[:8]}")
+
         return "\n".join(lines)
 
     async def _t_list_deliverables(self, sor, p, pid):