[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>

tests/entrypoints/test_omni_entrypoints.py

@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+
 from __future__ import annotations
 
 import queue
@@ -97,9 +100,11 @@ class FakeAsyncOmniEngine:
     ) -> None:
         self.model = model
         self.config_path = None
-        self.stage_configs: list[Any] = []
         self.stage_metadata = stage_metadata or [THREE_STAGE_META[-1]]
         self.num_stages = len(self.stage_metadata)
+        self.stage_configs = [
+            StageConfig(stage_id=i, model_stage="dummy-model").to_omegaconf() for i in range(self.num_stages)
+        ]
         self.default_sampling_params_list = default_sampling_params_list or [
             SamplingParams(max_tokens=8) for _ in range(self.num_stages)
         ]