[Core] Composable parallel: Phase 1 strategy overlay (TP/DP/stage-replica) (RFC #4084) (#4281)

Signed-off-by: Kushan A. <kahmadian@nvidia.com>
Signed-off-by: kushanam <kushanam@users.noreply.github.com>
Signed-off-by: Kushan A <kahmadian@nvidia.com>
Signed-off-by: kahmadian <kahmadian@users.noreply.github.com>
Co-authored-by: kushanam <kushanam@users.noreply.github.com>
Co-authored-by: kahmadian <kahmadian@users.noreply.github.com>

tests/test_config_factory.py

@@ -1721,7 +1721,7 @@ class TestAuraOmniDeploy:
     def test_aura_omni_deploy_resolves_four_native_stages(self):
         pipeline_cfg = StageConfigFactory.resolve_pipeline_config("aura_omni")
 
-        stages = StageConfigFactory._create_from_registry(
+        stages, _ = StageConfigFactory._create_from_registry(
             "qwen3_tts",
             pipeline_cfg,
             cli_overrides={},
@@ -1943,11 +1943,12 @@ class TestSentinelDefaultPrecedence:
             model_type,
             Q3_OMNI_ALL_STAGES_HF_CONFIG,
         )
-        return StageConfigFactory._create_from_registry(
+        stages, _ = StageConfigFactory._create_from_registry(
             "qwen3_omni_moe",
             pipeline_cfg,
             cli_overrides=cli_overrides,
         )
+        return stages
 
     def test_typed_kwarg_overrides_yaml(self):
         stages = self._stages({"max_num_seqs": 999})