refactor: simplify upload UI and enforce glb-only preview

components/ModelViewer.tsx

@@ -9,9 +9,12 @@ interface ModelViewerProps {
 }
 
 export default function ModelViewer({ url, filename, size }: ModelViewerProps) {
+  const canPreview = filename.toLowerCase().endsWith('.glb')
   const [Scene, setScene] = useState<React.ComponentType<{ url: string }> | null>(null)
 
   useEffect(() => {
+    if (!canPreview) return
+
     let cancel = false
 
     import('./SceneViewer').then((mod) => {
@@ -19,7 +22,17 @@ export default function ModelViewer({ url, filename, size }: ModelViewerProps) {
     })
 
     return () => { cancel = true }
-  }, [])
+  }, [canPreview])
+
+  if (!canPreview) {
+    return (
+      <div className="w-full h-[450px] bg-black-800 border border-white/20 rounded-xl overflow-hidden flex items-center justify-center">
+        <p className="text-sm text-gray-400 px-6 text-center">
+          La preview 3D locale est disponible uniquement pour les fichiers <span className="font-mono">.glb</span>.
+        </p>
+      </div>
+    )
+  }
 
   if (!Scene) {
     return (
@@ -42,4 +55,4 @@ export default function ModelViewer({ url, filename, size }: ModelViewerProps) {
       <Scene url={url} />
     </div>
   )
-}
+}