Set formatter to prettier and update format_on_save option

ansible/templates/zed.jsonc

@@ -10,6 +10,7 @@
   // #############################################
   // ## Theming                                 ##
   // #############################################
+  "formatter": "prettier",
   "context_servers": {
     "mcp-server-context7": {
       "source": "extension",
@@ -96,7 +97,7 @@
   "hide_mouse": "on_typing",
   "on_last_window_closed": "quit_app",
   "ensure_final_newline_on_save": true,
-  "format_on_save": "prettier",
+  "format_on_save": "on",
   "tab_size": 2,
   "inlay_hints": {
     "enabled": true,