feat: guild discovery

[onerandomusername]

Summary

Implements https://github.com/discord/discord-api-docs/pull/1762

Checklist

• [x] If code changes were made, then they have been tested
  • [x] I have updated the documentation to reflect the changes
  • [x] I have formatted the code properly by running task lint or pre-commit run --all-files
• [ ] This PR fixes an issue
• [x] This PR adds something new (e.g. new method or parameters)
• [ ] This PR is a breaking change (e.g. methods or parameters removed/renamed)
• [ ] This PR is not a code change (e.g. documentation, README, ...)

[onerandomusername]

The documentation for discovery management has not been documented and the PR was closed, so I'll leave this open for a little while and probably close it.

[shiftinv]

Going to close this one, since there doesn't seem to be any reasonable chance that the api-docs PR will be reopened at this point.