fix(cleanup): F02 清理失败记录含任务编号的告警，孤儿 xlsx 按保留期回收

- process_formula_export 失败清理受阻时记录不含敏感数据的 WARNING（任务编号+文件名），
  并保留 job.path 使残留文件仍可追踪，而不是清空后失联
- cleanup_formula_exports 新增孤儿 .xlsx 回收：超过 24h 保留期且不属于任何
  未过期成功任务的文件统一回收（覆盖失败任务残留、任务行被级联删除两种来源），
  不触碰仍处于活动任务的文件
- 测试：注入 unlink 权限错误→任务失败状态仍保存+告警可见；恢复权限后回收成功
  且其他任务文件不受影响；失败任务残留/任务行已删/未过期成功/近期文件/非 UUID 命名

tests/test_formula_cleanup.py

@@ -1,4 +1,5 @@
 import os
+import uuid
 from datetime import timedelta
 
 import pytest
@@ -27,6 +28,12 @@ def cleanup_root(settings, tmp_path):
     return tmp_path / "formula-exports", dataset, user
 
 
+def _aged(path, hours=25):
+    stamp = (timezone.now() - timedelta(hours=hours)).timestamp()
+    os.utime(path, (stamp, stamp))
+    return path
+
+
 def test_cleanup_expires_jobs_and_removes_files(cleanup_root):
     root, dataset, user = cleanup_root
     path = root / str(user.pk) / "expired.xlsx"
@@ -55,8 +62,7 @@ def test_cleanup_removes_only_stale_temporary_files(cleanup_root):
     stale, recent = user_dir / "stale.tmp", user_dir / "recent.tmp"
     stale.touch()
     recent.touch()
-    old = timezone.now().timestamp() - 25 * 3600
-    os.utime(stale, (old, old))
+    _aged(stale)
 
     call_command("cleanup_formula_exports")
 
@@ -81,3 +87,71 @@ def test_cleanup_does_not_delete_files_outside_export_root(cleanup_root, tmp_pat
     job.refresh_from_db()
     assert job.status == "expired"
     assert outside.read_bytes() == b"keep"
+
+
+def test_cleanup_reclaims_failed_job_leftover_after_retention(cleanup_root):
+    root, dataset, user = cleanup_root
+    job = FormulaExport.objects.create(dataset=dataset, user=user, status="failed")
+    path = root / str(user.pk) / f"{job.pk}.xlsx"
+    path.parent.mkdir(parents=True)
+    path.write_bytes(b"leftover")
+    job.path = str(path)
+    job.save(update_fields=["path"])
+    _aged(path)
+
+    call_command("cleanup_formula_exports")
+
+    job.refresh_from_db()
+    assert not path.exists()
+    assert job.path == ""
+
+
+def test_cleanup_keeps_workbook_of_unexpired_succeeded_job(cleanup_root):
+    root, dataset, user = cleanup_root
+    job = FormulaExport.objects.create(
+        dataset=dataset,
+        user=user,
+        status="succeeded",
+        expires_at=timezone.now() + timedelta(hours=1),
+    )
+    path = root / str(user.pk) / f"{job.pk}.xlsx"
+    path.parent.mkdir(parents=True)
+    path.write_bytes(b"active")
+    job.path = str(path)
+    job.save(update_fields=["path"])
+    _aged(path)
+
+    call_command("cleanup_formula_exports")
+
+    assert path.read_bytes() == b"active"
+    job.refresh_from_db()
+    assert job.path == str(path)
+
+
+def test_cleanup_reclaims_orphan_whose_job_row_was_deleted(cleanup_root):
+    root, _, user = cleanup_root
+    user_dir = root / str(user.pk)
+    user_dir.mkdir(parents=True)
+    orphan = user_dir / f"{uuid.uuid4()}.xlsx"
+    orphan.write_bytes(b"orphan")
+    recent = user_dir / f"{uuid.uuid4()}.xlsx"
+    recent.write_bytes(b"recent orphan")
+    _aged(orphan)
+
+    call_command("cleanup_formula_exports")
+
+    assert not orphan.exists()
+    assert recent.exists()
+
+
+def test_cleanup_ignores_non_uuid_workbook_names(cleanup_root):
+    root, _, user = cleanup_root
+    user_dir = root / str(user.pk)
+    user_dir.mkdir(parents=True)
+    odd = user_dir / "notes.xlsx"
+    odd.write_bytes(b"keep")
+    _aged(odd)
+
+    call_command("cleanup_formula_exports")
+
+    assert odd.exists()