整合求解器活动监控与步长回归证据

同步远端 PNL0003 诊断和大采样网格能力，语义合并活动感知的 60 秒真停滞判定与旧后端 15 分钟兼容兜底。

纳管热路径优化、15 单元运行证据、浏览器与 API 报告，并补充北京时间更新日志和遗留问题。

app/main.py

@@ -3,7 +3,7 @@ from __future__ import annotations
 from collections.abc import AsyncIterator, Callable, Iterator, Mapping
 from contextlib import asynccontextmanager
 import csv
-from dataclasses import dataclass
+from dataclasses import dataclass, field
 from datetime import datetime, timezone
 import io
 import json
@@ -24,6 +24,7 @@ from pydantic import BaseModel, ConfigDict, Field, ValidationError
 
 from app.simulation.performance import performance_span, profile_phase, profile_run
 from app.simulation.property_cache import property_cache_run
+from app.simulation.solvers.solver import SolverActivityTracker
 from app.system_xml import (
     SystemXmlDocument,
     SystemXmlValidationReport,
@@ -86,6 +87,9 @@ SimulationTaskStatus = Literal[
 class SimulationTaskRecord:
     simulation_id: str
     cancel_event: threading.Event
+    activity_tracker: SolverActivityTracker = field(
+        default_factory=SolverActivityTracker
+    )
     status: SimulationTaskStatus = "queued"
     cancel_reason: SimulationCancelReason | None = None
     result: dict[str, object] | None = None
@@ -574,6 +578,7 @@ def _simulation_task_snapshot(task: SimulationTaskRecord) -> dict[str, object]:
             "cancelReason": task.cancel_reason,
             "result": task.result,
             "error": task.error,
+            **task.activity_tracker.snapshot().as_dict(),
         }
 
 
@@ -681,6 +686,7 @@ def run_system_xml_simulation(
     xml_bytes: bytes,
     progress_callback: SimulationProgressEmitter | None = None,
     cancel_check: Callable[[], bool] | None = None,
+    activity_tracker: SolverActivityTracker | None = None,
 ) -> dict[str, object]:
     with property_cache_run() as property_cache:
         with profile_run() as trace:
@@ -688,6 +694,7 @@ def run_system_xml_simulation(
                 xml_bytes,
                 progress_callback,
                 cancel_check,
+                activity_tracker,
             )
 
     performance = trace.snapshot()
@@ -712,6 +719,7 @@ def _run_system_xml_simulation_profiled(
     xml_bytes: bytes,
     progress_callback: SimulationProgressEmitter | None = None,
     cancel_check: Callable[[], bool] | None = None,
+    activity_tracker: SolverActivityTracker | None = None,
 ) -> dict[str, object]:
     from app.simulation.solvers.algebraic import AlgebraicSolveError
     from app.simulation.solvers.solver import SolveIVPConfig
@@ -774,6 +782,7 @@ def _run_system_xml_simulation_profiled(
             sample_step=document.simulation.sample_step,
             progress_callback=report_system_progress,
             cancel_check=cancel_check,
+            activity_tracker=activity_tracker,
         )
     except SimulationPreparationError as exc:
         raise HTTPException(
@@ -862,6 +871,9 @@ def simulation_event_stream(
     latest_message = "正在等待仿真任务启动"
     latest_simulated_time: float | None = None
     latest_total_time: float | None = None
+    activity_tracker = (
+        task.activity_tracker if task is not None else SolverActivityTracker()
+    )
 
     def emit_progress(
         progress: int,
@@ -889,6 +901,7 @@ def simulation_event_stream(
             event["simulatedTime"] = latest_simulated_time
         if latest_total_time is not None:
             event["totalTime"] = latest_total_time
+        event.update(activity_tracker.snapshot().as_dict())
         events.put(event)
 
     def worker() -> None:
@@ -899,28 +912,44 @@ def simulation_event_stream(
                 xml_bytes,
                 emit_progress,
                 task.cancel_event.is_set if task is not None else None,
+                activity_tracker,
             )
             if task is not None:
                 result = _mark_simulation_task_result(task, result)
             result_status = str(result.get("status", "completed"))
+            final_simulated_time = result.get("simulatedUntil")
+            final_activity_kind = (
+                "complete" if result_status == "completed" else result_status
+            )
+            if activity_tracker.snapshot().activity_kind != final_activity_kind:
+                activity_tracker.record_phase(
+                    final_activity_kind,
+                    (
+                        float(final_simulated_time)
+                        if isinstance(final_simulated_time, (int, float))
+                        and isfinite(final_simulated_time)
+                        else None
+                    ),
+                )
             result_messages = {
                 "completed": "仿真完成",
                 "stopped": "仿真已由用户终止，已保留部分结果",
                 "stalled": "仿真因进度连接异常而终止，已保留部分结果",
                 "failed": "仿真异常终止，已保留可用的部分结果",
             }
-            events.put(
-                {
-                    "event": "result",
-                    "progress": 100 if result_status == "completed" else latest_progress,
-                    "phase": result_status,
-                    "message": result_messages.get(result_status, "仿真任务结束"),
-                    "simulatedTime": result.get("simulatedUntil"),
-                    "totalTime": result.get("requestedStopTime"),
-                    "result": result,
-                }
-            )
+            result_event = {
+                "event": "result",
+                "progress": 100 if result_status == "completed" else latest_progress,
+                "phase": result_status,
+                "message": result_messages.get(result_status, "仿真任务结束"),
+                "simulatedTime": result.get("simulatedUntil"),
+                "totalTime": result.get("requestedStopTime"),
+                "result": result,
+            }
+            result_event.update(activity_tracker.snapshot().as_dict())
+            events.put(result_event)
         except HTTPException as exc:
+            activity_tracker.record_phase("failed")
             detail = exc.detail
             message = (
                 str(detail.get("message", "仿真失败"))
@@ -935,10 +964,12 @@ def simulation_event_stream(
                 "message": message,
                 "detail": detail,
             }
+            error_event.update(activity_tracker.snapshot().as_dict())
             if task is not None:
                 _mark_simulation_task_error(task, error_event)
             events.put(error_event)
         except Exception as exc:  # pragma: no cover - last-resort stream guard
+            activity_tracker.record_phase("failed")
             error_event = {
                 "event": "error",
                 "progress": latest_progress,
@@ -947,6 +978,7 @@ def simulation_event_stream(
                 "message": "仿真服务发生未预期错误。",
                 "detail": str(exc),
             }
+            error_event.update(activity_tracker.snapshot().as_dict())
             if task is not None:
                 _mark_simulation_task_error(task, error_event)
             events.put(error_event)
@@ -964,16 +996,18 @@ def simulation_event_stream(
             try:
                 event = events.get(timeout=SIMULATION_STREAM_HEARTBEAT_SECONDS)
             except queue.Empty:
+                heartbeat_event = {
+                    "event": "progress",
+                    "progress": latest_progress,
+                    "phase": latest_phase,
+                    "message": latest_message,
+                    "heartbeat": True,
+                    "simulatedTime": latest_simulated_time,
+                    "totalTime": latest_total_time,
+                }
+                heartbeat_event.update(activity_tracker.snapshot().as_dict())
                 yield json.dumps(
-                    {
-                        "event": "progress",
-                        "progress": latest_progress,
-                        "phase": latest_phase,
-                        "message": latest_message,
-                        "heartbeat": True,
-                        "simulatedTime": latest_simulated_time,
-                        "totalTime": latest_total_time,
-                    },
+                    heartbeat_event,
                     ensure_ascii=False,
                     separators=(",", ":"),
                 ) + "\n"