"Extra devel is not defined" error during dev setup.

[Vleyked]

closes #55635

This PR updates the scripts/tools/initialize_virtualenv.py script to fix the "Extra devel is not defined" error during dev setup.

Summary of the fixes made:

• Changed the default dependency group from devel to dev in the check_for_package_extras() function
• Updated the help documentation to reflect the correct dependency group names available in the project
• Installed the missing system package pkg-config which was required for building MySQL client libraries
• Change --extra devel to --group dev in UV sync command

This aligns with UV's dependency groups in pyproject.toml and resolves the error "Extra devel is not defined in the project's optional-dependencies table" when setting up the development environment.

The script now installs dev dependencies without errors.

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[Vleyked]

Post-fix