style(orion): align report header footer and page layout

validation-suite/frontend/atlas/app/loading.tsx

@@ -0,0 +1,15 @@
+import { BrandLogo } from "@/components/brand/brand-logo";
+
+export default function Loading() {
+  return (
+    <main className="flex min-h-screen items-center justify-center bg-background">
+      <div className="rounded-lg border border-border bg-surface p-8 shadow-soft">
+        <BrandLogo />
+        <div className="mt-6 flex items-center justify-center gap-3 text-text-light">
+          <span className="spinner" />
+          <span>Validation Suite wird geladen.</span>
+        </div>
+      </div>
+    </main>
+  );
+}