Add PHP code block type expectation to PromptCodeBlockExtractor class

spec0 - should this be in review?

Needs review?

I'll close the issue otherwise in 2 weeks.

See comment above

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We are doing some issue management housekeeping and adding/removing components.

We are removing the "Code" component and want people to categorize issues with the best module/submodule component.

Moving this issue to "AI Core module".

See 📌 Update AI module project components Active for more details.