feat: Added support for HTTP status in ResponseCache

[sk757a]

Description
Implementation of storing and returning HTTP status for a cached response.

Currently, ResponseCache always returns 200 OK, regardless of the controller's response.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

[mergeable]

Hi there, sk757a! 👋

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[michalsn]

Nice addition. I'm not sure whether this should be classified as a bug or a feature, but I'm fine treating it as a feature.

Please add a changelog entry here: https://github.com/codeigniter4/CodeIgniter4/blob/4.7/user_guide_src/source/changelogs/v4.7.0.rst#libraries