Remove working-directory from Upload Release Asset step to ensure
gh CLI uses the correct repository (flash-attention-prebuild-wheels)
instead of the cloned flash-attention repository.
- Replace manual GITHUB_REF string manipulation with github.ref_name in _build_windows.yml, _build_windows_code_build.yml, and _build_windows_self_host.yml.
- Add _build_windows_self_host.yml for self-hosted Windows wheel builds.
- Integrate self-hosted Windows build job into main build.yml workflow.
- Update create_matrix.py to include and enable Windows self-hosted build matrix.
- Implement comprehensive cleanup steps in the self-hosted runner workflow to ensure a clean state for subsequent runs.