fix: disable open keymap split editor from toolbar

The complete support for split editor is yet to be added to IDE2.
For now, this commit turns off opening the keymaps in the JSON
split editor. So that it cannot get the primary IDE2 layout into an
inconsistent state.

Closes arduino/arduino-ide#1850

Signed-off-by: Akos Kitta <a.kitta@arduino.cc>

arduino-ide-extension/src/browser/theia/keymaps/keymaps-frontend-contribution.ts

@@ -1,14 +1,20 @@
+import { CommandRegistry } from '@theia/core/lib/common/command';
+import { MenuModelRegistry } from '@theia/core/lib/common/menu/menu-model-registry';
+import { nls } from '@theia/core/lib/common/nls';
 import { injectable } from '@theia/core/shared/inversify';
-import { MenuModelRegistry } from '@theia/core';
 import {
-  KeymapsFrontendContribution as TheiaKeymapsFrontendContribution,
   KeymapsCommands,
+  KeymapsFrontendContribution as TheiaKeymapsFrontendContribution,
 } from '@theia/keymaps/lib/browser/keymaps-frontend-contribution';
 import { ArduinoMenus } from '../../menu/arduino-menus';
-import { nls } from '@theia/core/lib/common';
 
 @injectable()
 export class KeymapsFrontendContribution extends TheiaKeymapsFrontendContribution {
+  override registerCommands(registry: CommandRegistry): void {
+    super.registerCommands(registry);
+    registry.unregisterCommand(KeymapsCommands.OPEN_KEYMAPS_JSON_TOOLBAR.id);
+  }
+
   override registerMenus(menus: MenuModelRegistry): void {
     menus.registerMenuAction(ArduinoMenus.FILE__ADVANCED_SUBMENU, {
       commandId: KeymapsCommands.OPEN_KEYMAPS.id,