v1.0.0

fix: grant contents:write so the tag-triggered release step can publish

The first v1.0.0 tag push failed at "Publish Release" with "Resource
not accessible by integration" — new repos default GITHUB_TOKEN to
read-only contents, which blocks softprops/action-gh-release from
creating the Release/uploading the asset.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>