Add iOS & Android build + frontend fixes for desktop

frontend/src/utils/native.js

@@ -0,0 +1,38 @@
+// Capacitor bootstrap — no-ops on the web, configures native shell on mobile.
+// Plugins are dynamic-imported so the web bundle isn't penalized.
+
+let initStarted = false;
+
+export function isNativeApp() {
+  return typeof window !== 'undefined' && Boolean(window.Capacitor?.isNativePlatform?.());
+}
+
+export async function initNativeShell() {
+  if (initStarted || !isNativeApp()) return;
+  initStarted = true;
+
+  try {
+    const { StatusBar, Style } = await import('@capacitor/status-bar');
+    await StatusBar.setBackgroundColor({ color: '#0f766e' }).catch(() => {});
+    await StatusBar.setStyle({ style: Style.Light }).catch(() => {});
+  } catch {
+    /* plugin not present — fine on web */
+  }
+
+  try {
+    const { SplashScreen } = await import('@capacitor/splash-screen');
+    await SplashScreen.hide({ fadeOutDuration: 250 }).catch(() => {});
+  } catch {
+    /* plugin not present — fine on web */
+  }
+
+  try {
+    const { App } = await import('@capacitor/app');
+    App.addListener('backButton', ({ canGoBack }) => {
+      if (canGoBack) window.history.back();
+      else App.exitApp();
+    });
+  } catch {
+    /* plugin not present — fine on web */
+  }
+}