feat: Option to change screen recording resolution #119

Is your feature request related to a problem? Please describe.
Most services have a file size limit, which is especially annoying with screen recordings, as these easily get into the Gigabytes in a short amount of recording time.

Describe the solution you'd like
I'd like a way to change the resolution of the screen recording, either to just record at a lower resolution, or to scale down the finished recording before uploading it.

Describe alternatives you've considered
QuickTime Player also allows for screen recording, just without as many features like auto uploading, but it at least has an export button, which allows you to change the quality of your recording.

Additional context
Let me know if you need any.