feat: enforce primary header filenames

[kanikasharma-18]

Resolves #13658.

Description

What is the purpose of this pull request?

This pull request:

• adds lint support for enforcing primary header filename conventions for packages containing an include/ directory
• requires the primary header filename to match the package name, with hyphens converted to underscores
• preserves hyphens in parent package directories
• allows additional headers with arbitrary filenames
• adds test coverage for missing, valid, and invalid primary header filenames
• documents the include/ directory in the package structure documentation

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Add lint support for enforcing header filename conventions #13658

Questions

Any questions for reviewers of this pull request?

No.

Other

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No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• Read, understood, and followed the contributing guidelines

AI Assistance

When authoring the changes proposed in this PR, did you use any kind of AI assistance?

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• No

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• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

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I used AI assistance for research and understanding of the implementation.

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[kanikasharma-18]

@kgryte @Planeshifter @nakul-krishnakumar

Hi! I’ve opened this PR for #13658. It adds lint support for enforcing primary header filename conventions, along with the relevant tests and documentation.

Would appreciate a review when you get a chance. Thank you!