feat: Implement better get_or_fetch

[Lumabots]

Summary

Information

• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters). Implement better get_or_fetch #1856
• This PR is a breaking change (e.g. methods or parameters removed/renamed).
• This PR is not a code change (e.g. documentation, README, typehinting,
  examples, ...).

Checklist

• I have searched the open pull requests for duplicates.
• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
• If type: ignore comments were used, a comment is also left explaining why.
• I have updated the changelog to include these changes.

[Lumabots]

feat from #1856

[Lumabots]

still not ready have some bug like : NameError: name 'VoiceChannel' is not defined
ig because of the type checking, i'll have to find a way to import it without circular import

[Paillat-dev]

@Lumabots You can import it inside of the function where you use it directly instead of importing it at the top

[Lumabots]

@Lumabots You can import it inside of the function where you use it directly instead of importing it at the top

Well ig the issue come from the definition for the typevar, so will that resolve it ?

[Lumabots]

should be ready for review

[Lumabots]

just need to specify that this is breaking inside the changelog cos of modification of get_or_fetch and removal of get_or_fetch_user

[Soheab]

Little nitpicks and consistency issues with the docs. LGTM code-wise.

[Copilot]

Pull Request Overview

This PR implements a better version of the get_or_fetch utility function with improved type safety and error handling. The update introduces new convenience methods on Guild and Client classes while maintaining backward compatibility through deprecation warnings.

• Replaces string-based object type specification with type class parameters for better type safety
• Adds new get_or_fetch methods to Guild and Client classes for easier access
• Maintains backward compatibility by deprecating the old string-based approach

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
discord/utils.py	Rewrites the get_or_fetch function with type-safe overloads and helper functions
discord/guild.py	Adds get_or_fetch method and get_emoji helper method to Guild class
discord/client.py	Adds get_or_fetch method and deprecates get_or_fetch_user
CHANGELOG.md	Documents the new features and deprecations

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[Paillat-dev]

See copilot comment, wtf