chore: fix N806 lint - rename _RESAMPLE_VIDEO_INTERVAL to lowercase

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/question_gen/pipeline_v2.py

@@ -330,7 +330,7 @@ async def _process_one_slot(
     返回:
         GeneratedQuestion（通过全部检查）或 None（重出耗尽）。
     """
-    _RESAMPLE_VIDEO_INTERVAL = 1
+    resample_video_interval = 1
 
     async with sem:
         strategy = get_strategy(slot.task_type)
@@ -341,8 +341,8 @@ async def _process_one_slot(
         current_video_id = slot.video_id
 
         for attempt in range(1, config.retry_limit + 1):
-            # 连续失败 _RESAMPLE_VIDEO_INTERVAL 次后换视频
-            if attempt > 1 and (attempt - 1) % _RESAMPLE_VIDEO_INTERVAL == 0 and all_trees:
+            # 连续失败 resample_video_interval 次后换视频
+            if attempt > 1 and (attempt - 1) % resample_video_interval == 0 and all_trees:
                 alt_ids = [v for v in all_trees if v != current_video_id]
                 if alt_ids:
                     current_video_id = rng.choice(alt_ids)