Added onboarding + a lightweight install banner to both the mobile login screen and the settings screen, with Android/Chromium

install prompt support and iOS “Share → Add to Home Screen” guidance. Also added a small helper + tests to decide
  when/which banner variant should show, and shared copy in common.json.

resources/js/admin/mobile/lib/installPrompt.ts

@@ -0,0 +1,25 @@
+export type InstallOutcome = 'accepted' | 'dismissed' | 'unknown';
+
+export type BeforeInstallPromptEvent = Event & {
+  prompt: () => Promise<void>;
+  userChoice: Promise<{ outcome: InstallOutcome; platform: string }>;
+};
+
+export function isIosDevice(userAgent: string): boolean {
+  return /iphone|ipad|ipod/i.test(userAgent);
+}
+
+export function resolveStandaloneDisplayMode(matchMediaStandalone: boolean, navigatorStandalone?: boolean): boolean {
+  return matchMediaStandalone || navigatorStandalone === true;
+}
+
+export function getStandaloneStatus(): boolean {
+  if (typeof window === 'undefined') {
+    return false;
+  }
+
+  const matchMediaStandalone = window.matchMedia?.('(display-mode: standalone)')?.matches ?? false;
+  const navigatorStandalone = typeof navigator !== 'undefined' ? (navigator as Navigator & { standalone?: boolean }).standalone : undefined;
+
+  return resolveStandaloneDisplayMode(matchMediaStandalone, navigatorStandalone);
+}