[Docs] Remove stale stage config references (#6270)

Signed-off-by: zwhzzz0821 <2831474076@qq.com>

docs/design/module/model_integration.md

@@ -42,7 +42,7 @@ and execution behavior to stable runtime contracts.
 ### MODEL-INV-001: Registration is explicit
 
 **Rule:** A model integration MUST declare how its model class, loader, input
-processor, and stage configuration are selected.
+processor, and pipeline configuration are selected.
 
 ### MODEL-INV-002: Model code does not route stages
 

docs/design/module/vllm_omni_config.md

@@ -10,9 +10,8 @@ owners:
 primary_code_paths:
   - vllm_omni/config/**
   - vllm_omni/deploy/**
-  - vllm_omni/model_executor/stage_configs/**
-related_code_paths:
-  - vllm_omni/platforms/*/stage_configs/**
+  - vllm_omni/model_executor/models/*/pipeline.py
+related_code_paths: []
 depends_on: []
 validation_paths:
   - tests/config/**
@@ -95,7 +94,7 @@ parallel input is effective for a diffusion stage.
 ## Safe-change guide while deferred
 
 Changes should trace every affected producer to its runtime consumer and test
-the structured, legacy, CLI, and deployment paths that are actually supported.
+the structured pipeline, CLI, and deployment paths that are actually supported.
 For inherited vLLM fields, tests should separately cover constructor behavior
 and effective `EngineArgs` projection. Do not infer a stable contract from
 this placeholder page.