feat(freight:backoffice): added login page and basic authorization

apps/edr-freight-web/backoffice/src/components/LoadingScreen.tsx

@@ -0,0 +1,14 @@
+const LoadingScreen = () => {
+  return (
+    <div className="flex min-h-screen items-center justify-center bg-background px-6">
+      <div className="rounded-2xl border border-border bg-card px-8 py-6 text-center shadow-sm">
+        <p className="text-sm font-medium uppercase tracking-[0.2em] text-muted-foreground">
+          EDR Freight Backoffice
+        </p>
+        <p className="mt-3 text-lg font-semibold text-foreground">Loading...</p>
+      </div>
+    </div>
+  );
+};
+
+export default LoadingScreen;