feat: multiple item imports in use statement

[ghost]

Description

Implement multiple item imports in use statement: use foo::{bar, hello}.

Summary

Added support for multiple item imports in the use statement, allowing for more flexible and targeted module imports. Updated the parser, AST, and desugaring logic to handle the new syntax.

Additional Context

PR Checklist

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[jfecher]

This solution looks pretty good and is quite simple because of the desugaring. I do think we should parse UseTrees recursively which should clean up the parsing code a little and allow us to support recursive { and } in imports.

[jfecher]

This PR looks very good. I did run into some minor usability concerns while testing it though. Once we fix these last issues I think it is all set!

[jfecher]

Closing this PR, it is superseded by #1548

[jfecher]

Reviewing this PR I got into a bit of a rabbit hole with handling the cases for use dep::dep::dep, nested blocks use {{{{foo}}}};, and their implications. I now think we should just merge this PR and we can look to fix the use dep::dep::dep; and other corner cases later since they will rarely be encountered in actual code anyway.

[jfecher]

Looks like clippy caught some code which can be simplified