feat: Add raw equivalent of on_presence_update - on_raw_presence_update.

[elenakrittik]

Summary

Resolves #1152

This is (apparently) the first time i am working with raw events, so i may have made some serious mistakes. I tried my best to follow how other existing raw events work (and from my quick tests everything works fine), but please correct me if i did something wrong.

Checklist

• If code changes were made, then they have been tested
  • I have updated the documentation to reflect the changes
  • I have formatted the code properly by running pdm lint
  • I have type-checked the code by running pdm pyright
• This PR fixes an issue
• 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, ...)

[shiftinv]

Thanks for the PR!

Could you add the new event to the description of Intents.presences?

These comments are mainly related to documentation - I'm still not fully decided on which fields to deserialize into the raw event, but this already looks pretty good.