Feat: V4.0 new endpoints and more

[Droid00000]

Summary

This pull request aims to update the 4.0 staging branch with changes from the master branch and add new API endpoints. It also includes a few other miscellaneous changes, such as further deprecating references to Rest-Client, deprecating references to user accounts, and removing deprecated API endpoints.

Added

• Application endpoints
• Auto-moderation endpoints
• Application emoji endpoints
• Entitlement endpoints
• Guild scheduled event endpoints
• Followup message endpoints
• Sku endpoints
• Poll endpoints
• Soundboard endpoints
• Onboarding endpoints
• Get guild role endpoint
• Modify guild mfa-level endpoint
• New audit log entry types.
• Discordrb::CDN namespace.
• Misc new fields for endpoint parameters.
• Documentation for every API endpoint parameter.
• Application command localization support from this PR (As discussed in DAPI)
• Faraday-multipart gem. (since it's no longer a part of Faraday middleware)
• Explicitly add Base64 gem as a dependency as it will no longer be part of the standard library as of Ruby version 3.4.0.
• Every change made between the last commit on the 4.0 branch (November 2021) to the present day.

Changed

• Updated Faraday to version 2.0.1
• Moved voice endpoints into their own file to be more consistent with the API docs.
• Moved message endpoints into their own file to be more consistent with the API docs.
• Updated the way we process the bot token to more closely align with the client class

Removed

• lib/discordrb/api.rb
• Process token method.
• Account type parameter on initialize bot.
• Updating status/presence via the REST API.
• Faraday middleware gem as it's been deprecated.
• Removes the batch edit application command permissions endpoint as its been disabled and requests to it will not return a valid response.

Todo

• RBS type signatures.
• Update and cleanup specs.

[Droid00000]

I'll close this for now because I believe it would be best to split this PR across multiple PRs. At the moment, this is a massive PR with many different changes that should be documented to a degree that is greater than a single comment, along with the fact that this would probably be a pain in the ass to review as is.