crew_add.go: Use gt-crew-role instead of per-instance role bead polecat/manager.go: Add RoleBead field pointing to gt-polecat-role Per agent-as-bead design, role beads are shared class definitions. Each agent bead references its role via the role_bead field/slot. Fixes gt-ne9he 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>