Get thumbnail from app (#68)

* Renamed multipart filed name 'files' to 'assetData'. 
* Added an additional field name of 'thumbnailData' to multipart form.
* Implemented upload mechanism for thumbnail directly from the mobile client.
* Removed dead code
* Implemented a version checking mechanism.

server/src/modules/background-task/background-task.processor.ts

@@ -41,7 +41,6 @@ export class BackgroundTaskProcessor {
   async extractExif(job: Job) {
     const { savedAsset, fileName, fileSize }: { savedAsset: AssetEntity; fileName: string; fileSize: number } =
       job.data;
-
     const fileBuffer = await readFile(savedAsset.originalPath);
 
     const exifData = await exifr.parse(fileBuffer);