[Feature]: per-folder settings

[NicolaSmaniotto]

Describe the feature you'd like added

I'd like to set different settings for specific folders.

Additional context

The idea is to define special rules to create "watchlist" folders.

If a file is in "my" folder, I'd like the plugin to ignore all watches except my own (it should stay there until I watch it). In this way there is no issue if someone else watches it before me. For example, files in /movies/ should be kept for 30 days after the last watch, but files in /watchlist-nicola/ should be kept for 30 days after the last watch by me, ignoring everyone else's. This could be accomplished by setting users to "Acknowledge" and selecting only mine, so the current filtering logic can still be applied.

Ideally, there should be a global option that allows setting some default values, and then specific folder overrides if needed to keep files for different amounts of time, ignoring some users, etc...

From what I understand of how the plugin works, this will require some radical changes to its core, and also to the settings page. I don't expect this to be implemented any time soon, I just wanted to throw the idea out there and discuss it.