feat: polish Shopee update checks

tests/test_db.py

@@ -100,6 +100,14 @@ class DbTests(TempDirMixin, unittest.TestCase):
             self.assertEqual("generated", generated.stage)
             self.assertEqual("新标题", generated.new_title)
 
+            db.mark_failed(task.id, "generate", "标题需调整", path=db_path)
+            db.update_generated_title(task.id, "人工标题", path=db_path)
+            edited = db.list_tasks(path=db_path)[0]
+            self.assertEqual("generated", edited.stage)
+            self.assertEqual("pending", edited.status)
+            self.assertEqual("人工标题", edited.new_title)
+            self.assertIsNone(edited.last_error)
+
             db.set_applied(task.id, False, "按钮禁用", path=db_path)
             apply_failed = db.list_tasks(path=db_path)[0]
             self.assertEqual("generated", apply_failed.stage)
@@ -112,6 +120,8 @@ class DbTests(TempDirMixin, unittest.TestCase):
             self.assertEqual("success", applied.status)
             self.assertEqual(1, applied.committed)
             self.assertEqual(2, applied.apply_attempts)
+            with self.assertRaises(db.DbError):
+                db.update_generated_title(task.id, "线上后改标题", path=db_path)
 
         self.assert_removed(temp_dir)