fix(frontend): definite-height overlay chain so absolute panels anchor to viewport

services/frontend/src/components/shared/page-transition.tsx

@@ -11,5 +11,7 @@ export function PageTransition({
   children: React.ReactNode;
   className?: string;
 }) {
-  return <div className={cn("animate-fade-up", className)}>{children}</div>;
+  return (
+    <div className={cn("animate-fade-up h-full", className)}>{children}</div>
+  );
 }

services/frontend/src/components/shell/constellation-frame.tsx

@@ -68,7 +68,7 @@ export function ConstellationFrame({
         {/* Overlay content region — scenes place floating panels inside. */}
         <main className="pointer-events-none absolute inset-0 z-10 overflow-y-auto overscroll-contain">
           {/* no pointer-events here: empty areas stay click-through to the sky */}
-          <div className="min-h-full">{children}</div>
+          <div className="h-full">{children}</div>
         </main>
       </div>
     </SceneGraphProvider>