Add an easter egg to the app

src/app/loading.tsx

@@ -0,0 +1,17 @@
+export default function Loading() {
+  return (
+    <main className="relative flex min-h-screen items-center justify-center overflow-hidden">
+      <div className="pointer-events-none absolute inset-0">
+        <div className="absolute -left-24 -top-24 h-72 w-72 rounded-full bg-primary/20 blur-3xl" />
+        <div className="absolute right-0 bottom-0 h-72 w-72 rounded-full bg-accent/30 blur-3xl" />
+      </div>
+      <div className="relative flex flex-col items-center gap-4 rounded-3xl border border-border/60 bg-card/70 px-10 py-12 shadow-lg">
+        <div className="h-10 w-10 animate-spin rounded-full border-2 border-muted-foreground border-t-transparent" />
+        <div className="text-sm font-semibold uppercase tracking-[0.3em] text-muted-foreground">
+          Loading
+        </div>
+        <div className="text-xs text-muted-foreground">Preparing the gallery.</div>
+      </div>
+    </main>
+  );
+}