Make release publish job idempotent when tag release already exists

[Copilot]

The publish job in the release workflow failed on run 33848099285 because gh release create exits non-zero when a release for the tag already exists. This change makes the publish step safe for reruns and duplicate tag-triggered executions.

• Root-cause handling

  • Replaces unconditional gh release create with existence-aware logic.
  • Detects whether ${GITHUB_REF_NAME} already has a GitHub release.

• Publish behavior update

  • If release exists: upload artifacts via gh release upload --clobber.
  • If release does not exist: create release with existing metadata flow (--title, --generate-notes).

• Scope

  • Touches only .github/workflows/release.yml in the publish step; build matrix and artifact production paths remain unchanged.

if gh release view "${GITHUB_REF_NAME}" --repo "${GITHUB_REPOSITORY}" >/dev/null 2>&1; then
  gh release upload "${GITHUB_REF_NAME}" --repo "${GITHUB_REPOSITORY}" --clobber dist/*
else
  gh release create "${GITHUB_REF_NAME}" --repo "${GITHUB_REPOSITORY}" --title "${GITHUB_REF_NAME}" --generate-notes dist/*
fi

[xylophoneengine]

thank you