fix: Use rig's configured prefix for agent bead IDs (gt-kdy77, gt-ihvq0)
Added WithPrefix variants to agent bead ID functions:
- AgentBeadIDWithPrefix(prefix, rig, role, name)
- WitnessBeadIDWithPrefix, RefineryBeadIDWithPrefix
- CrewBeadIDWithPrefix, PolecatBeadIDWithPrefix
Updated callers to use rig's configured prefix:
- crew_add.go: reads r.Config.Prefix for crew worker beads
- rig/manager.go: uses prefix param for witness/refinery beads
- doctor/agent_beads_check.go: uses prefix from routes.jsonl
This allows non-gastown rigs (like beads with bd- prefix) to have
properly-prefixed agent beads.
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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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