[Edge][WP1] Add edge deploy profile and deploy_profile selector

* vllm_omni/deploy/edge/qwen3_tts.yaml: single-device Qwen3-TTS profile with a
  ramped codec chunk schedule (2->4->8->16->25 frames) that removes the ~80 ms
  playback stall of the default 1->25 schedule, decode batch 1, max_num_seqs 4.
* deploy_profile="edge" (Omni/AsyncOmni kwarg, --deploy-profile CLI, headless
  serve) resolves vllm_omni/deploy/<profile>/<model_type>.yaml; mutually
  exclusive with deploy_config; explicit profiles never fall back silently.
* tests/helpers/stage_config.py: modify_stage_config anchors a relative
  base_config before writing the temp YAML so overlay-derived configs resolve.
* async_omni_engine.py also carries the init-timeline hooks used by WP2.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

tests/config/test_deploy_profiles.py

@@ -0,0 +1,83 @@
+"""Tests for named deploy profiles (``vllm_omni/deploy/<profile>/<model_type>.yaml``)."""
+
+from __future__ import annotations
+
+from pathlib import Path
+from unittest import mock
+
+import pytest
+
+from vllm_omni.config.stage_config import _DEPLOY_DIR, load_deploy_config, resolve_deploy_yaml
+from vllm_omni.entrypoints import utils as entry_utils
+from vllm_omni.model_executor.stage_input_processors.chunk_size_utils import parse_chunk_ramp
+
+pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
+
+EDGE_QWEN3_TTS = _DEPLOY_DIR / "edge" / "qwen3_tts.yaml"
+
+
+def test_edge_profile_file_exists():
+    assert EDGE_QWEN3_TTS.exists()
+    assert "edge" in entry_utils.available_deploy_profiles()
+    assert "edge" in entry_utils.available_deploy_profiles("qwen3_tts")
+
+
+def test_edge_profile_resolves_two_stages_on_one_device():
+    cfg = load_deploy_config(EDGE_QWEN3_TTS)
+    assert len(cfg.stages) == 2
+    assert all(stage.devices == "0" for stage in cfg.stages)
+    assert cfg.stages[0].max_num_seqs == 4
+    assert cfg.stages[1].max_num_seqs == 4
+    assert cfg.async_chunk is True
+    # Inherited from the base config: stage 0 keeps its sampling defaults.
+    assert cfg.stages[0].default_sampling_params is not None
+
+
+def test_edge_profile_ramp_parses_and_ends_at_steady_chunk():
+    raw = resolve_deploy_yaml(EDGE_QWEN3_TTS)
+    extra = raw["connectors"]["connector_of_shared_memory"]["extra"]
+    steady = int(extra["codec_chunk_frames"])
+    ramp = parse_chunk_ramp(extra, steady=steady)
+    assert ramp == [2, 4, 8, 16, 25]
+    assert ramp[-1] == steady
+    assert extra["decode_batch_max_size"] == 1
+    assert extra["codec_left_context_frames"] == 72
+
+
+def test_deploy_path_for_profile_lookup():
+    assert entry_utils.deploy_path_for_profile("qwen3_tts", "edge") == EDGE_QWEN3_TTS
+    assert entry_utils.deploy_path_for_profile("qwen3_tts", "no_such_profile") is None
+    assert entry_utils.deploy_path_for_profile("no_such_model", "edge") is None
+    assert entry_utils.deploy_path_for_profile("qwen3_tts", "") is None
+
+
+def test_resolve_deploy_profile_path_uses_default_stem():
+    with mock.patch.object(entry_utils, "resolve_model_config_path", return_value=str(_DEPLOY_DIR / "qwen3_tts.yaml")):
+        assert entry_utils.resolve_deploy_profile_path("Qwen/Qwen3-TTS-12Hz-0.6B-CustomVoice", "edge") == str(
+            EDGE_QWEN3_TTS
+        )
+        with pytest.raises(FileNotFoundError, match="no_such_profile"):
+            entry_utils.resolve_deploy_profile_path("Qwen/Qwen3-TTS-12Hz-0.6B-CustomVoice", "no_such_profile")
+
+
+def test_apply_deploy_profile_translates_and_rejects_conflicts():
+    with mock.patch.object(entry_utils, "resolve_model_config_path", return_value=str(_DEPLOY_DIR / "qwen3_tts.yaml")):
+        args = {"deploy_profile": "edge", "other": 1}
+        out = entry_utils.apply_deploy_profile("Qwen/Qwen3-TTS-12Hz-0.6B-CustomVoice", args)
+        assert out["deploy_config"] == str(EDGE_QWEN3_TTS)
+        assert "deploy_profile" not in out and out["other"] == 1
+        with pytest.raises(ValueError, match="mutually exclusive"):
+            entry_utils.apply_deploy_profile("m", {"deploy_profile": "edge", "deploy_config": "x.yaml"})
+    # No profile: untouched.
+    assert entry_utils.apply_deploy_profile("m", {"deploy_config": "x.yaml"}) == {"deploy_config": "x.yaml"}
+
+
+def test_modify_stage_config_keeps_relative_base_config_resolvable():
+    from tests.helpers.stage_config import modify_stage_config
+
+    tmp_yaml = modify_stage_config(str(EDGE_QWEN3_TTS), updates={"stages": {0: {"max_num_seqs": 1}}})
+    raw = resolve_deploy_yaml(Path(tmp_yaml))
+    assert len(raw["stages"]) == 2
+    cfg = load_deploy_config(Path(tmp_yaml))
+    assert cfg.stages[0].max_num_seqs == 1
+    assert cfg.stages[1].max_num_seqs == 4