feat: add entitlement/app subscription support

[AstreaTSS]

Pull Request Type

• [x] Feature addition
• [ ] Bugfix
• [ ] Documentation update
• [ ] Code refactor
• [ ] Tests improvement
• [ ] CI/CD pipeline enhancement
• [ ] Other: [Replace with a description]

Description

Adds support for entitlements, otherwise known as App Subscriptions, into interactions.py.

Changes

• Added the Entitlement object.
• Added entitlement creation, update, and deletion events.
• Added send_premium_required to InteractionContext. I'm unsure of the naming here, but I can't think of another good name to use.
• Added entitlements as an attribute to BaseInteractionContext.
• Added HTTP methods to list entitlements, as well as to create and delete test entitlements.
  • Methods have been added to Client to allow normal users to use them.

Related Issues

Resolves #1613.

Test Scenarios

Python Compatibility

• [ ] I've ensured my code works on Python 3.10.x
• [x] I've ensured my code works on Python 3.11.x

Checklist

• [x] I've run the pre-commit code linter over all edited files
• [x] I've tested my changes on supported Python versions
• [ ] I've added tests for my code, if applicable
• [x] I've updated / added documentation, where applicable

[AstreaTSS]

Thanks to @Wolfhound905, I was able to test it and fix a few bugs. This should be ready for review.

[FayeDel]

LGTM, as far as I can see and test to a degree, merging 👍🏻