fix(prime): add boot role detection for proper context injection (#370)

Boot sessions run in `deacon/dogs/boot/` but were incorrectly detected
as deacon role because the deacon check matched first. This caused Boot
to receive Deacon's context instead of Boot-specific context.

Changes:
- Add RoleBoot constant
- Add boot path detection before deacon check in detectRole()
- Add boot case in buildRoleAnnouncement()
- Add boot case in getAgentIdentity() (returns "boot")
- Add boot case in getAgentBeadID() (uses deacon's bead as subprocess)

The boot.md.tmpl template already exists and will now be used.

Fixes #318

internal/cmd/prime.go

@@ -29,6 +29,7 @@ type Role string
 const (
 	RoleMayor    Role = "mayor"
 	RoleDeacon   Role = "deacon"
+	RoleBoot     Role = "boot"
 	RoleWitness  Role = "witness"
 	RoleRefinery Role = "refinery"
 	RolePolecat  Role = "polecat"
@@ -276,6 +277,13 @@ func detectRole(cwd, townRoot string) RoleInfo {
 		return ctx
 	}
 
+	// Check for boot role: deacon/dogs/boot/
+	// Must check before deacon since boot is under deacon directory
+	if len(parts) >= 3 && parts[0] == "deacon" && parts[1] == "dogs" && parts[2] == "boot" {
+		ctx.Role = RoleBoot
+		return ctx
+	}
+
 	// Check for deacon role: deacon/
 	if len(parts) >= 1 && parts[0] == "deacon" {
 		ctx.Role = RoleDeacon
@@ -496,6 +504,8 @@ func buildRoleAnnouncement(ctx RoleContext) string {
 		return "Mayor, checking in."
 	case RoleDeacon:
 		return "Deacon, checking in."
+	case RoleBoot:
+		return "Boot, checking in."
 	case RoleWitness:
 		return fmt.Sprintf("%s Witness, checking in.", ctx.Rig)
 	case RoleRefinery:
@@ -530,6 +540,8 @@ func getAgentIdentity(ctx RoleContext) string {
 		return "mayor"
 	case RoleDeacon:
 		return "deacon"
+	case RoleBoot:
+		return "boot"
 	case RoleWitness:
 		return fmt.Sprintf("%s/witness", ctx.Rig)
 	case RoleRefinery:
@@ -599,6 +611,9 @@ func getAgentBeadID(ctx RoleContext) string {
 		return beads.MayorBeadIDTown()
 	case RoleDeacon:
 		return beads.DeaconBeadIDTown()
+	case RoleBoot:
+		// Boot uses deacon's bead since it's a deacon subprocess
+		return beads.DeaconBeadIDTown()
 	case RoleWitness:
 		if ctx.Rig != "" {
 			prefix := beads.GetPrefixForRig(ctx.TownRoot, ctx.Rig)