When --on is specified, the first argument is a formula name:
gt sling shiny --on gt-abc123
This applies the formula to existing work, creating wisp scaffolding
that shapes execution of the target bead.
Changes:
- Add Formula field to SlungWork wisp type
- Add --on flag to gt sling command
- Verify both bead and formula exist before slinging
- Update dry-run output to show formula info
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>