fix(panel): anchor disk phase evidence to heartbeat mtime, not run start

On auto-retry, attempt2 resets the heartbeat to 采集中 and refetches, but
attempt1's completion files (registry etc.) are newer than the run start —
they overrode the fresh heartbeat and showed 推送/收尾 while the browser
was actively fetching. Disk evidence must beat the heartbeat's own mtime
to override; attempt resets naturally re-anchor the baseline.

web/app.py

@@ -592,35 +592,38 @@ def _harvest_phase(source):
     except OSError:
         return None, None
 
-    # 1) 真实阶段文件(进程自己写的)——但仅当它比磁盘证据新时才采信
-    #    (会话偶尔忘记翻牌,磁盘信号(manifest/summaries/registry)是客观事实)
+    # 1) 真实阶段文件(进程自己写的)——磁盘证据必须比心跳最后写入时间新才能覆盖它。
+    #    基准锚在心跳而非任务开始:自动重试的 attempt2 会重置心跳为"采集中"重新抓取,
+    #    attempt1 的收尾文件(registry 等)虽比任务开始新,但比新心跳旧,不得污染新阶段。
+    phase_file = LOG_DIR / f"{source}.phase"
+    hb_txt, hb_mtime = "", None
+    if phase_file.exists():
+        try:
+            hb_txt = phase_file.read_text(encoding="utf-8").strip()
+            hb_mtime = mtime(phase_file)
+        except OSError:
+            hb_txt, hb_mtime = "", None
+    baseline = hb_mtime or start
+
     def disk_phase_and_mtime():
         if not (day_dir and day_dir.is_dir()):
             return None, None
         reg = mtime(day_dir / "registry.json")
-        if reg and reg > start:
+        if reg and reg > baseline:
             return "推送/收尾", reg
         summ = mtime(day_dir / ".summaries.json")
-        if summ and summ > start:
+        if summ and summ > baseline:
             return "摘要生成", summ
         mani = mtime(day_dir / ".manifest.json")
-        if mani and mani > start:
+        if mani and mani > baseline:
             return "摘要生成", mani
         return None, None
 
-    phase_file = LOG_DIR / f"{source}.phase"
-    hb_txt, hb_mtime = "", None
-    if phase_file.exists():
-        try:
-            hb_txt = phase_file.read_text(encoding="utf-8").strip()
-            hb_mtime = mtime(phase_file)
-        except OSError:
-            hb_txt, hb_mtime = "", None
     dp, dp_mtime = disk_phase_and_mtime()
     if hb_txt and hb_mtime:
         if not dp or hb_mtime >= dp_mtime:
             return start, hb_txt
-        return start, dp  # 心跳比磁盘证据旧:信磁盘
+        return start, dp  # 磁盘证据比心跳新:信磁盘(会话忘翻牌的场景)
     if dp:
         return start, dp
     # 3) 无信号:中性显示,不猜