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Description

Add an ast-grep rule to the CI autofix workflow to automatically convert all Optional[T] type hints to the modern T | None syntax in Python files.

Motivation

The Optional[T] type hint from typing is considered deprecated in favor of the more concise and readable T | None syntax introduced in Python 3.10. This refactor will:

• Modernize the codebase to use current Python type hinting best practices
• Improve code readability with shorter, cleaner type annotations
• Reduce imports from the typing module
• Ensure consistency across the codebase with automated CI enforcement

Additional Context

This change adds an ast-grep rule to the existing autofix CI workflow that will automatically convert type hints during pull requests, ensuring all new and modified code uses the modern syntax.