fix(chat): support body and content fields in world and DM chat messages; feat(audio): add sound toggle switch and mute controls

scripts/controls_modal.gd

@@ -13,6 +13,7 @@ const CONTROLS_DATA = [
 	{"key": "E", "action": "Interact with objects & chests"},
 	{"key": "T / Enter", "action": "Open In-World Chat"},
 	{"key": "Tab / F1", "action": "Friends & Social Panel"},
+	{"key": "M", "action": "Toggle Sound (Mute / Unmute)"},
 	{"key": "F2", "action": "Creator Studio / World Editor"},
 	{"key": "F11 / Alt+Enter", "action": "Toggle Fullscreen"},
 	{"key": "ESC", "action": "Pause Menu / Go Back / Close Modal"},