Enforce new AI Disclosure in PR Checklist

[DanGould]

Checking 'a human read this' has proven insufficient. Let's try another experiment where we ask for disclosure. Perhaps this can help us learn more effective AI development techniques at the same time by sharing what we've done.

Inspired by Ghostty: ghostty-org/ghostty#8289
Close #990

Pull Request Checklist

Please confirm the following before requesting review:

• A human has reviewed every single line of this code before opening the PR (no auto-generated, unreviewed LLM/robot submissions).
• I have read CONTRIBUTING.md and rebased my branch to produce hygienic commits.

[coveralls]

Pull Request Test Coverage Report for Build 17300854314

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 85.775%

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Totals
Change from base Build 17299929671:	0.0%
Covered Lines:	8014
Relevant Lines:	9343

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💛 - Coveralls

[arminsabouri]

Ack 67bf7d7

[benalleng]

Ack 67bf7d7 I know it can be tedious but I think we should try to lead the charge trying to be thorough with these disclosures, I think it could also be helpful for new contributors to see both
A. that we take these disclosures seriously
and
B. give devs a way to share some knowledge about how we are using AI in our everyday workflow