Running pinned Biome in CI for PR comments

[lgarron]

Per the following, it is documented that npx biome ci should be printing line-specific information for PRs in GitHub.

• Support Workflow Commands #441
• https://biomejs.dev/recipes/continuous-integration/
• https://biomejs.dev/blog/biome-v1-5/#the-command-biome-ci-now-prints-diagnostics-in-github-prs

However, I have never gotten this to work. Recent test: https://github.com/lgarron/permission.site/pull/2/changes

• Passing --reporter github does print something, but it just prints File content differs from formatting output associated with the top of a file, not actual failure locations.
• Adding the pull-requests: write permission doesn't seem to make a difference.

Also, https://github.com/marketplace/actions/run-biome-with-reviewdog is a non-starter because it uses its own hardcoded Biome instead of @biomejs/biome from pinned project dependencies.

Presumably I'm missing something, but I'm not sure where else to look.