PHP 8.6: Add polyfills for clamp and ValueError functions for PHP compatibility

[Soean]

This pull request adds a polyfill for the new PHP 8.6 clamp() function to ensure compatibility with older PHP versions. It also introduces a helper function to throw the appropriate error type depending on the PHP version.

New function polyfills and helpers:

• Added _wp_throw_value_error() to throw a ValueError on PHP 8.0+ or an InvalidArgumentException on PHP 7.x, providing consistent error handling for polyfills.
• Added a polyfill for the clamp() function, which restricts a value within a specified minimum and maximum, including input validation and appropriate error throwing for invalid arguments.

Trac ticket: https://core.trac.wordpress.org/ticket/65143

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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Props soean.

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[github-actions]

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[mukeshpanchal27]

Why ignore?