Switch to ty for type checking

[gerlero]

No description provided.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (55acd68) to head (eee9300).

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #86   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
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  Files            3         3           
  Lines          352       352           
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  Hits           352       352           

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[Copilot]

Pull Request Overview

This PR switches the type checker from mypy to ty for the multicollections project. The change involves updating dependencies, type ignore comments, and fixing various type checking issues that arise with the new type checker.

• Replace mypy with ty as the project's type checker
• Update type ignore comments from mypy syntax to ty syntax
• Fix type checking issues revealed by ty's different analysis

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pyproject.toml	Replace mypy dependency with ty
README.md	Update badge from mypy to ty
tests/test_multicollections.py	Remove unnecessary type ignore comment
tests/minimalimpl.py	Update type ignore comments to ty syntax
multicollections/abc.py	Update type ignore comments and fix type checking issues
multicollections/init.py	Update type ignore comments and fix multi-line expression formatting

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