feat: default crew name to 'max', support town-level override

- Add DefaultCrewName constant ('max') to config package
- Add default_crew_name field to MayorConfig for town-level override
- Update gt rig add to resolve crew name: --crew flag > town config > default
- Update help text to reflect new default

Priority: --crew flag > MayorConfig.DefaultCrewName > config.DefaultCrewName ('max')

internal/cmd/rig.go

@@ -48,7 +48,7 @@ This creates a rig container with:
   - plugins/              Rig-level plugin directory
   - refinery/rig/         Canonical main clone
   - mayor/rig/            Mayor's working clone
-  - crew/main/            Default human workspace
+  - crew/max/             Default human workspace
   - witness/              Witness agent directory
   - polecats/             Worker directory (empty)
 
@@ -141,7 +141,7 @@ func init() {
 	rigCmd.AddCommand(rigShutdownCmd)
 
 	rigAddCmd.Flags().StringVar(&rigAddPrefix, "prefix", "", "Beads issue prefix (default: derived from name)")
-	rigAddCmd.Flags().StringVar(&rigAddCrew, "crew", "main", "Default crew workspace name")
+	rigAddCmd.Flags().StringVar(&rigAddCrew, "crew", "", "Crew workspace name (default: from town config or 'max')")
 
 	rigResetCmd.Flags().BoolVar(&rigResetHandoff, "handoff", false, "Clear handoff content")
 	rigResetCmd.Flags().BoolVar(&rigResetMail, "mail", false, "Clear stale mail messages")
@@ -163,6 +163,18 @@ func runRigAdd(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("not in a Gas Town workspace: %w", err)
 	}
 
+	// Resolve crew name: --crew flag > town config > default constant
+	crewName := rigAddCrew
+	if crewName == "" {
+		// Try loading MayorConfig for default_crew_name
+		mayorConfigPath := filepath.Join(townRoot, "mayor", "config.json")
+		if mayorCfg, err := config.LoadMayorConfig(mayorConfigPath); err == nil && mayorCfg.DefaultCrewName != "" {
+			crewName = mayorCfg.DefaultCrewName
+		} else {
+			crewName = config.DefaultCrewName
+		}
+	}
+
 	// Load rigs config
 	rigsPath := filepath.Join(townRoot, "mayor", "rigs.json")
 	rigsConfig, err := config.LoadRigsConfig(rigsPath)
@@ -188,7 +200,7 @@ func runRigAdd(cmd *cobra.Command, args []string) error {
 		Name:        name,
 		GitURL:      gitURL,
 		BeadsPrefix: rigAddPrefix,
-		CrewName:    rigAddCrew,
+		CrewName:    crewName,
 	})
 	if err != nil {
 		return fmt.Errorf("adding rig: %w", err)
@@ -210,12 +222,12 @@ func runRigAdd(cmd *cobra.Command, args []string) error {
 	fmt.Printf("  ├── plugins/          (rig-level plugins)\n")
 	fmt.Printf("  ├── refinery/rig/     (canonical main)\n")
 	fmt.Printf("  ├── mayor/rig/        (mayor's clone)\n")
-	fmt.Printf("  ├── crew/%s/        (your workspace)\n", rigAddCrew)
+	fmt.Printf("  ├── crew/%s/        (your workspace)\n", crewName)
 	fmt.Printf("  ├── witness/\n")
 	fmt.Printf("  └── polecats/\n")
 
 	fmt.Printf("\nNext steps:\n")
-	fmt.Printf("  cd %s/crew/%s    # Work in your clone\n", filepath.Join(townRoot, name), rigAddCrew)
+	fmt.Printf("  cd %s/crew/%s    # Work in your clone\n", filepath.Join(townRoot, name), crewName)
 	fmt.Printf("  bd ready                 # See available work\n")
 
 	return nil

internal/config/types.go

@@ -17,11 +17,12 @@ type TownConfig struct {
 // MayorConfig represents town-level behavioral configuration (mayor/config.json).
 // This is separate from TownConfig (identity) to keep configuration concerns distinct.
 type MayorConfig struct {
-	Type    string           `json:"type"`              // "mayor-config"
-	Version int              `json:"version"`           // schema version
-	Theme   *TownThemeConfig `json:"theme,omitempty"`   // global theme settings
-	Daemon  *DaemonConfig    `json:"daemon,omitempty"`  // daemon settings
-	Deacon  *DeaconConfig    `json:"deacon,omitempty"`  // deacon settings
+	Type            string           `json:"type"`                        // "mayor-config"
+	Version         int              `json:"version"`                     // schema version
+	Theme           *TownThemeConfig `json:"theme,omitempty"`             // global theme settings
+	Daemon          *DaemonConfig    `json:"daemon,omitempty"`            // daemon settings
+	Deacon          *DeaconConfig    `json:"deacon,omitempty"`            // deacon settings
+	DefaultCrewName string           `json:"default_crew_name,omitempty"` // default crew name for new rigs
 }
 
 // DaemonConfig represents daemon process settings.
@@ -38,6 +39,9 @@ type DeaconConfig struct {
 // CurrentMayorConfigVersion is the current schema version for MayorConfig.
 const CurrentMayorConfigVersion = 1
 
+// DefaultCrewName is the default name for crew workspaces when not overridden.
+const DefaultCrewName = "max"
+
 // RigsConfig represents the rigs registry (mayor/rigs.json).
 type RigsConfig struct {
 	Version int                 `json:"version"`