Remove useModelRouter experimental flag (#13593)

packages/cli/src/config/settingsSchema.ts

@@ -1281,16 +1281,6 @@ const SETTINGS_SCHEMA = {
           'Enables extension loading/unloading within the CLI session.',
         showInDialog: false,
       },
-      useModelRouter: {
-        type: 'boolean',
-        label: 'Use Model Router',
-        category: 'Experimental',
-        requiresRestart: true,
-        default: true,
-        description:
-          'Enable model routing to route requests to the best model based on complexity.',
-        showInDialog: true,
-      },
       codebaseInvestigatorSettings: {
         type: 'object',
         label: 'Codebase Investigator Settings',