[Glitch] Use LayoutType from is_mobile in actions/app

Port 5bc8e2d1fdc3f1b1a0b9af5aed762d44e048250c to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/actions/app.ts

@@ -1,7 +1,8 @@
 import { createAction } from '@reduxjs/toolkit';
+import type { LayoutType } from '../is_mobile';
 
 type ChangeLayoutPayload = {
-  layout: 'mobile' | 'single-column' | 'multi-column';
+  layout: LayoutType;
 };
 export const changeLayout =
   createAction<ChangeLayoutPayload>('APP_LAYOUT_CHANGE');