ZFC #4: Replace daemon identity parsing with agent self-registration

Implements role-based lifecycle configuration where agent types self-register
via role beads instead of hardcoded identity string parsing in the daemon.

Changes:
- Add RoleConfig struct with lifecycle fields (session_pattern, work_dir_pattern,
  needs_pre_sync, start_command, env_vars)
- Add ParseRoleConfig/FormatRoleConfig/ExpandRolePattern to beads package
- Add role bead ID helpers (RoleBeadID, MayorRoleBeadID, etc.)
- Refactor daemon to use single parseIdentity function as ONLY place where
  identity strings are parsed
- Daemon now looks up role beads to get lifecycle config, with fallback to
  defaults when role bead is missing or has no config
- Updated all role beads (mayor, deacon, witness, refinery, crew, polecat)
  with structured lifecycle configuration fields
- Add comprehensive unit tests for RoleConfig parsing and expansion

This makes the daemon ZFC-compliant by trusting what agents self-report in
their role beads rather than encoding agent-specific knowledge in Go code.

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

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

internal/beads/beads.go

@@ -888,3 +888,68 @@ func IsAgentSessionBead(beadID string) bool {
 		return false
 	}
 }
+
+// Role bead ID naming convention:
+//   gt-<role>-role
+//
+// Examples:
+//   - gt-mayor-role
+//   - gt-deacon-role
+//   - gt-witness-role
+//   - gt-refinery-role
+//   - gt-crew-role
+//   - gt-polecat-role
+
+// RoleBeadID returns the role bead ID for a given role type.
+// Role beads define lifecycle configuration for each agent type.
+func RoleBeadID(roleType string) string {
+	return "gt-" + roleType + "-role"
+}
+
+// MayorRoleBeadID returns the Mayor role bead ID.
+func MayorRoleBeadID() string {
+	return RoleBeadID("mayor")
+}
+
+// DeaconRoleBeadID returns the Deacon role bead ID.
+func DeaconRoleBeadID() string {
+	return RoleBeadID("deacon")
+}
+
+// WitnessRoleBeadID returns the Witness role bead ID.
+func WitnessRoleBeadID() string {
+	return RoleBeadID("witness")
+}
+
+// RefineryRoleBeadID returns the Refinery role bead ID.
+func RefineryRoleBeadID() string {
+	return RoleBeadID("refinery")
+}
+
+// CrewRoleBeadID returns the Crew role bead ID.
+func CrewRoleBeadID() string {
+	return RoleBeadID("crew")
+}
+
+// PolecatRoleBeadID returns the Polecat role bead ID.
+func PolecatRoleBeadID() string {
+	return RoleBeadID("polecat")
+}
+
+// GetRoleConfig looks up a role bead and returns its parsed RoleConfig.
+// Returns nil, nil if the role bead doesn't exist or has no config.
+func (b *Beads) GetRoleConfig(roleBeadID string) (*RoleConfig, error) {
+	issue, err := b.Show(roleBeadID)
+	if err != nil {
+		if errors.Is(err, ErrNotFound) {
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	if issue.Type != "role" {
+		return nil, fmt.Errorf("bead %s is not a role bead (type: %s)", roleBeadID, issue.Type)
+	}
+
+	return ParseRoleConfig(issue.Description), nil
+}