Two improvements:
1. gt crew start now infers rig from cwd when first arg is not a valid
rig name (gt-czltv). Previously, running `gt crew start bob` from
within a rig directory would fail because "bob" was treated as the
rig name. Now it checks if the arg is a valid rig first.
2. Refactored copyOverlay to shared rig.CopyOverlay utility:
- Eliminates code duplication between crew and polecat managers
- Preserves source file permissions instead of hardcoding 0644
- Follows PR #278 improvements
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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