refactor(qwen3_omni): inherit _maybe_apply_prompt_updates from the Qwen2.5-Omni processor

The vLLM 0.29 rewrite left Qwen3OmniMoeThinkerMultiModalProcessor with a
_maybe_apply_prompt_updates that is identical to the one on its first base,
Omni's Qwen2_5OmniThinkerMultiModalProcessor (same body modulo docstring).
The MRO is Omni Qwen3 -> Omni Qwen2.5 -> upstream Qwen3 -> upstream Qwen2.5
-> BaseMultiModalProcessor, so deleting the override resolves to the same
code; asserted with
Qwen3OmniMoeThinkerMultiModalProcessor._maybe_apply_prompt_updates is
Qwen2_5OmniThinkerMultiModalProcessor._maybe_apply_prompt_updates.

Validation: ruff and pre-commit on the file; the MRO assertion above;
tests/model_executor/models/{qwen3_omni,qwen2_5_omni} pass (20 + 81 tests).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MpXe2LeRrUQGjZfKFaocMZ
Signed-off-by: tzhouam <tzhouam@connect.ust.hk>

vllm_omni/model_executor/models/qwen3_omni/qwen3_omni_moe_thinker.py

@@ -705,47 +705,6 @@ class Qwen3OmniMoeThinkerMultiModalProcessor(
     # Preserve Omni's per-video overrides while inheriting upstream Qwen3's
     # audio processing through the shared, cooperative Qwen2.5 base.
 
-    def _maybe_apply_prompt_updates(
-        self,
-        mm_items: MultiModalDataItems,
-        prompt_ids: list[int],
-        mm_kwargs: MultiModalKwargsItems,
-        mm_prompt_updates: MultiModalPromptUpdates,
-    ) -> tuple[list[int], Mapping[str, list[PlaceholderFeaturesInfo]]]:
-        """
-        Qwen3-Omni reimplements this function to handle `use_audio_in_video`.
-        """
-        mm_item_counts = mm_items.get_all_counts()
-        self._validate_mm_kwargs(mm_kwargs, mm_item_counts)
-        self._validate_mm_updates(mm_prompt_updates, mm_item_counts)
-
-        video_use_audio_in_video = self._get_video_use_audio_in_video(mm_kwargs, mm_prompt_updates)
-        use_audio_in_video = any(video_use_audio_in_video)
-
-        if use_audio_in_video and "audio" in mm_prompt_updates:
-            filtered_updates = {k: v for k, v in mm_prompt_updates.items() if k != "audio"}
-            prompt_ids, mm_placeholders = self._apply_prompt_updates(
-                prompt_ids,
-                filtered_updates,
-            )
-            mm_placeholders = self._derive_audio_from_video_placeholders(
-                mm_placeholders,
-                mm_prompt_updates,
-                video_use_audio_in_video,
-            )
-        else:
-            prompt_ids, mm_placeholders = self._apply_prompt_updates(
-                prompt_ids,
-                mm_prompt_updates,
-            )
-
-        self._validate_mm_placeholders(
-            mm_placeholders,
-            mm_item_counts,
-        )
-
-        return prompt_ids, mm_placeholders
-
     def get_updates_use_audio_in_video(
         self,
         thinker_config: PretrainedConfig,