refactor: Upload file to storage, and then pass attachmentId to collections.import

This avoids having large file uploads going directly to the server and allows us to fetch it async into a worker process

app/utils/uploadFile.js

@@ -39,11 +39,13 @@ export const uploadFile = async (
     formData.append("file", file);
   }
 
-  await fetch(data.uploadUrl, {
+  const uploadResponse = await fetch(data.uploadUrl, {
     method: "post",
     body: formData,
   });
 
+  invariant(uploadResponse.ok, "Upload failed, try again?");
+
   return attachment;
 };