feat: add output path cli arg. change: copying and removing cache/out files

[carafelix]

closes #7

this PR changes the following:

• Add output path as a CLI arg
• Change default behavior to not clearing the output dir
• Add --clear-out flag for clearing the output dir, limits it to just .mp3 and .m3u files
• Copy files from cache to output as their are being downloaded
• Add --clear-cache flag, remove cached files as their are being copied to the output dir

[zeph1rus]

I do really appreciate you taking the time to work on this, for the reasons I put on on #7 I'm not going to merge this as it is, sorry

[carafelix]

@zeph1rus I reintroduced the clearance of the output dir as a flag. Consider merging 👍

[zeph1rus]

@carafelix There's a wider problem with numbering the files on subsequent runs, the way things are you'd end up with files with non unique or sequential numbers as pods get added - not your fault or problem, it's a requirement for my use cases. I'm pretty sure I know how I want to do that.

How do you want to handle that, would you like me to make the changes to make that work, and then you can rebase and put your changes on top, or you would you be ok with me adding some of the changes you made into that?

[carafelix]

or you would you be ok with me adding some of the changes you made into that?

I think best case is you do that branching from this? idk

Maybe merge this into somewhat like next, branch, do your changes and merge that into main?

Whatever suits your needs tbh. I'm okay with whatever.