"Mark as watched" feature

[d3caf]

Description

Currently, my friends have to text me a list of things they're done watching so I can remove them from my server to free up space.

Desired Behavior

1. Friends could mark their requested media as "watched"
2. The admin can receive a notification/webhook when this occurs
3. Some UI is available to show media that is safe to delete

--- future ideas

1. Potentially auto-delete things from sonarr/radarr if I haven't marked them as "keep" (via a tag or some config)
2. Potentially auto-mark-as-watched if the requester completes the media on plex?
3. Lotsa configuration and permissions

Additional Context

I've been thinking about attempting to implement this feature because right now, my friends need to text me lists of media they're done with so I can free up space.

Some thoughts/questions:

• Would this make sense to go on the Media entity?
  • like a watchedBy column with ID[] of users that watched the media
  • If a user manually marks as watched, their ID is added to the array
  • If auto-mark-as-watched, their ID is added to the array (perhaps via a task or webhook?)
  • Compare the watchedBy IDs to the IDs in the requests column
• Alternative: put it on the MediaRequest entity
  • this feels a little less intuitive since a request is never "watched"
  • but it could just be an extra status added to MediaRequestStatus

Code of Conduct

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