fix(ci): add release environment for npm OIDC publishing (#11)

## Summary
- Add `environment: release` to the publish job in `release-please.yml`
- Required for npm OIDC trusted publishing to match the environment
claim

## Setup required
- Create a `release` environment in GitHub: Settings > Environments >
New environment > "release"
- Update npm trusted publisher config to set Environment name to
`release`

## Test plan
- [ ] Merge this PR, then merge the next release-please PR to verify npm
publish succeeds

Author: tmchow

.github/workflows/release-please.yml

@@ -25,6 +25,7 @@ jobs:
     needs: release-please
     if: ${{ needs.release-please.outputs.release_created }}
     runs-on: ubuntu-latest
+    environment: release
     steps:
       - uses: actions/checkout@v6