[Model] Reduce MOSS-TTS Local intermediate output overhead

Keep internal talker control outputs FINAL_ONLY while codec audio remains incremental. Reapply pipeline sampling constraints after default streaming coercion, log routine coercions at debug level, and cover explicit/default parameters with regression tests. Document matched high-concurrency statistics settings.

Signed-off-by: Sy03 <1370724210@qq.com>

vllm_omni/model_executor/models/moss_tts/pipeline.py

@@ -1,8 +1,13 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+
 # Copyright 2026 OpenMOSS and the vLLM-Omni team. All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License").
 """Pipeline topology for all MOSS-TTS variants (2-stage: talker → codec)."""
 
+from vllm.sampling_params import RequestOutputKind
+
 from vllm_omni.config.stage_config import (
     PipelineConfig,
     StageExecutionType,
@@ -100,6 +105,10 @@ MOSS_TTS_LOCAL_PIPELINE = PipelineConfig(
             sampling_constraints={
                 "detokenize": False,
                 "stop_token_ids": [151645],
+                # The worker connector streams codes directly to the codec.
+                # This internal stage only needs to publish its terminal
+                # result; codec audio output remains incremental.
+                "output_kind": RequestOutputKind.FINAL_ONLY,
             },
         ),
         StagePipelineConfig(