Add endpoint for who upvoted (admin only)

[Ategon]

Requirements

• Is this a feature request? For questions or discussions use https://programming.dev/c/pangora
• Did you check to see if this issue already exists?
• Is this only a feature request? Do not put multiple feature requests in one issue.
• Is this a backend issue? Use the lemmy-ui repo for UI / frontend issues.

Is your proposal related to a problem?

Currently vote manipulation cant be caught without needing to dig through the database

Describe the solution you'd like.

This adds an admin only api endpoint that shows who upvoted or downvoted a post. Could also have one for seeing what a specific user has upvoted or downvoted recently.

Describe alternatives you've considered.

Sticking with the db - not all admins have access, its hard to navigate to catch people

Making the endpoint open to everyone - ruins the aspect of votes being more anonymous

Making the endpoint open to mods of the community - same as above, anyone can be a mod

Additional context

No response