fix: allow bot actors in amber auto-review workflow (#812)

## Summary

- Adds `allowed_bots: '*'` to the `anthropics/claude-code-action@v1`
step so the amber code review runs on PRs opened by bots (dependabot,
renovate, etc.)
- Previously the workflow would fail with: `Action failed with error:
Workflow initiated by non-human actor: dependabot (type: Bot)`

## Test plan

- [ ] Open or sync a dependabot PR and verify the amber-review job
completes successfully instead of failing

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

Author: Gkrumbach07

.github/workflows/amber-auto-review.yml

@@ -93,6 +93,7 @@ jobs:
           claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
           github_token: ${{ secrets.GITHUB_TOKEN }}
           allowed_non_write_users: '*'
+          allowed_bots: 'dependabot[bot],github-actions[bot]'
           claude_args: |
             --allowedTools "Bash(gh pr comment:*),Bash(gh pr diff:*),Bash(gh pr view:*),Bash(gh issue list:*)"
           prompt: |