fix(C-01): review fixes — missing keys, duplicate, GPS shock i18n

- Add missing keephead_enabled/disabled translation keys (BUG-001)
- Remove duplicate gui.tiedup.close key at line 403 (RISK-004)
- Fix GPS shock: use null addon + send GPS_ZONE_VIOLATION separately (RISK-001)

src/main/resources/assets/tiedup/lang/en_us.json

@@ -282,6 +282,8 @@
   "command.tiedup.clothes.unknown_layer": "Unknown layer: %s",
   "command.tiedup.clothes.layer_visible": "Wearer's %s layer is now visible",
   "command.tiedup.clothes.layer_hidden": "Wearer's %s layer is now hidden",
+  "command.tiedup.clothes.keephead_enabled": "Keep head mode enabled",
+  "command.tiedup.clothes.keephead_disabled": "Keep head mode disabled",
 
   "gui.tiedup.command_wand.title": "Command Wand",
   "gui.tiedup.command_wand.personality": "Personality",
@@ -400,7 +402,6 @@
 
   "gui.tiedup.slave_trader": "Slave Trader",
   "gui.tiedup.buy": "Buy",
-  "gui.tiedup.close": "Close",
   "gui.tiedup.no_captives_available": "No captives available for sale",
 
   "gui.tiedup.cell_manager": "Cell Manager",