Adds a new "AI Tags" button that opens a dialog to batch-generate
expertise tags using AI for all untagged projects in a selected round.
The feature uses the existing tag.batchTagProjects endpoint which:
- Only processes projects without existing tags
- Preserves any manually added tags
- Logs AI usage for cost tracking
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>