refactor: use hq- prefix for role bead references

Migrate all role bead references from gt-*-role to hq-*-role using
beads.RoleBeadIDTown() function. Role beads are stored in town beads
(~/gt/.beads/) with the hq- prefix.

Changes:
- internal/cmd/prime.go: Use RoleBeadIDTown() for all roles
- internal/doctor/agent_beads_check.go: Use RoleBeadIDTown() for rig agents
- internal/polecat/manager.go: Use RoleBeadIDTown("polecat")
- internal/cmd/crew_add.go: Use RoleBeadIDTown("crew")
- internal/beads/beads.go: Update comments to document hq- convention
- Templates: Update bd show gt-deacon to bd show hq-deacon

Note: Tmux session names remain as gt-* (runtime identifiers).
Bead IDs use hq-* for town-level agents (persistent storage).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/doctor/agent_beads_check.go

@@ -230,7 +230,7 @@ func (c *AgentBeadsCheck) Fix(ctx *CheckContext) error {
 				RoleType:   "witness",
 				Rig:        rigName,
 				AgentState: "idle",
-				RoleBead:   "gt-witness-role",
+				RoleBead:   beads.RoleBeadIDTown("witness"),
 			}
 			desc := fmt.Sprintf("Witness for %s - monitors polecat health and progress.", rigName)
 			if _, err := bd.CreateAgentBead(witnessID, desc, fields); err != nil {
@@ -244,7 +244,7 @@ func (c *AgentBeadsCheck) Fix(ctx *CheckContext) error {
 				RoleType:   "refinery",
 				Rig:        rigName,
 				AgentState: "idle",
-				RoleBead:   "gt-refinery-role",
+				RoleBead:   beads.RoleBeadIDTown("refinery"),
 			}
 			desc := fmt.Sprintf("Refinery for %s - processes merge queue.", rigName)
 			if _, err := bd.CreateAgentBead(refineryID, desc, fields); err != nil {
@@ -261,7 +261,7 @@ func (c *AgentBeadsCheck) Fix(ctx *CheckContext) error {
 					RoleType:   "crew",
 					Rig:        rigName,
 					AgentState: "idle",
-					RoleBead:   "gt-crew-role",
+					RoleBead:   beads.RoleBeadIDTown("crew"),
 				}
 				desc := fmt.Sprintf("Crew worker %s in %s - human-managed persistent workspace.", workerName, rigName)
 				if _, err := bd.CreateAgentBead(crewID, desc, fields); err != nil {