* feat: custom downloader (novel broken)
* fix: send headers to ffmpeg
ffmpeg can be a real bitch to work with
* fix: offline page for new download system
* feat: novel to new system | load freezing
* chore: clean manifest
* fix: notification incrementing
* feat: changing the downloads dir
This includes shadowed variables, unnecessary parameters, layouts with string literals, items that cause performance bottlenecks, and the merge of extension types into only the necessary separate classes.