[ROCm][CI] Stage C mirrors

[AndreasKaratzas]

Mirrored/gated test groups:

• V1 attention (H100-MI300)
• Engine
• OpenAI API correctness
• LM Eval Small Models
• Multi-Modal Models Pooling
• Spec Decode Draft Model
• Spec Decode Ngram + Suffix
• Spec Decode Speculators + MTP

Agent count: 6 x mi300_1, 2 x mi325_1

Notes:
Added Speculators Correctness and Extract Hidden States Integration in test-amd.yaml under mi300_1.

cc @kenroche

[gemini-code-assist]

Code Review

This pull request updates the Buildkite CI configuration to expand AMD GPU testing support for MI300 and MI325 hardware. Key changes include adding AMD mirror configurations across multiple test areas—such as attention, engine, entrypoints, and speculative decoding—and introducing new integration tests for speculators and hidden states. Reviewers suggested marking the new "Extract Hidden States Integration" test as optional to avoid CI bottlenecks and recommended updating parent step dependencies to include ROCm-specific files, ensuring that relevant code changes properly trigger the mirrored AMD tests.

[gemini-code-assist]

The parent step's source_file_dependencies should include all files that the mirrors depend on. Currently, changes to vllm/_aiter_ops.py, vllm/envs.py, or vllm/platforms/rocm.py will not trigger this step, and consequently, the AMD mirror will not run for those changes.

    - tests/v1/attention
    - vllm/_aiter_ops.py
    - vllm/envs.py
    - vllm/platforms/rocm.py

[gemini-code-assist]

The parent step is missing several dependencies that are explicitly required by the AMD mirror (e.g., vllm/platforms/rocm.py, vllm/_aiter_ops.py). If these files are modified, the parent step will not trigger, preventing the AMD mirror from running. The parent's source_file_dependencies should be the union of all dependencies across mirrors.

  - vllm/model_executor/models/whisper.py
  - vllm/model_executor/layers/
  - vllm/v1/attention/backends/
  - vllm/v1/attention/selector.py
  - vllm/_aiter_ops.py
  - vllm/platforms/rocm.py
  - vllm/model_executor/model_loader/

[gemini-code-assist]

The parent step should include vllm/platforms/rocm.py in its source_file_dependencies to ensure that ROCm-specific changes trigger the mirrored tests.

    - tests/v1/e2e/spec_decode/
    - vllm/platforms/rocm.py

[gemini-code-assist]

The parent step should include vllm/platforms/rocm.py in its source_file_dependencies to ensure that ROCm-specific changes trigger the mirrored tests.

    - tests/v1/e2e/spec_decode/
    - vllm/platforms/rocm.py

[gemini-code-assist]

The parent step should include vllm/platforms/rocm.py in its source_file_dependencies to ensure that ROCm-specific changes trigger the mirrored tests.

    - tests/v1/e2e/spec_decode/
    - vllm/platforms/rocm.py