feat: Expose ffmpeg options to users

[delucis]

compile-video.js currently hard codes various ffmpeg options when collating exported frames to a video file. It would make sense to expose some of these — e.g. video quality and format — in the settings passed to pellicola.

[PerryRylance]

I'll fork and add this if it's not available in the near future

[delucis]

A PR would be welcome if you’d like to make one — thanks!

[PerryRylance]

@delucis I have added videoCodec and crf as options locally, but I cannot publish a branch of this repository.

Are you able to allow me to make a pull request rather than forking?

[delucis]

You should fork and then make a PR from there! Let me know if you need any guidance.