fix: ensure uploaded files are valid

src/hooks/useMetadata.ts

@@ -11,22 +11,21 @@ export function useMetadata<T>(metadataPtr?: string): UseTRPCQueryResult<T, unkn
 export function useUploadMetadata(): UseMutationResult<{ url: string }, DefaultError, Record<string, unknown> | File> {
   return useMutation({
     mutationFn: async (data: Record<string, unknown> | File) => {
-      const formData = new FormData();
-
+      let uploadData;
       if (!(data instanceof File)) {
         const blob = new Blob([JSON.stringify(data)], {
           type: "application/json",
         });
 
-        formData.append("file", new File([blob], "metadata.json"));
+        uploadData = new File([blob], "metadata.json");
       } else {
-        formData.append("file", data);
+        uploadData = data;
       }
 
-      return fetch(`/api/blob?filename=${data instanceof File ? data.name : "metadata.json"}`, {
+      return fetch(`/api/blob?filename=${uploadData.name}`, {
         method: "POST",
         headers: { "Content-Type": "application/json" },
-        body: formData,
+        body: uploadData,
       }).then(async (r) => {
         if (!r.ok) {
           throw new Error("Network error");