Add offline transfer history and mobile app support

front/src/lib/app-shell.test.ts

@@ -0,0 +1,10 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { MOBILE_APP_MAX_WIDTH, shouldUseMobileApp } from './app-shell';
+
+test('shouldUseMobileApp enables the mobile shell below the width breakpoint', () => {
+  assert.equal(shouldUseMobileApp(MOBILE_APP_MAX_WIDTH - 1), true);
+  assert.equal(shouldUseMobileApp(MOBILE_APP_MAX_WIDTH), false);
+  assert.equal(shouldUseMobileApp(1280), false);
+});

front/src/lib/app-shell.ts

@@ -0,0 +1,5 @@
+export const MOBILE_APP_MAX_WIDTH = 768;
+
+export function shouldUseMobileApp(width: number) {
+  return width < MOBILE_APP_MAX_WIDTH;
+}