feat: support ai gateway

[kathmbeck]

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Summary

Provides initial AI gateway support for local dev. Tested locally with bootstrap changes.

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[github-actions]

📊 Benchmark results

Comparing with 961abee

• Dependency count: 1,078 ⬆️ 0.46% increase vs. 961abee
• Package size: 298 MB ⬆️ 0.12% increase vs. 961abee
• Number of ts-expect-error directives: 381 (no change)

[eduardoboucas]

Just pointing out that the pattern of having a util file for a specific chunk of tests, away from the test file itself, is not a pattern I've seen in this repo. Same goes for the usage of a function (createAIGatewayCheckFunction) to generate the functions to be tested, which feels like yet another abstraction on top of the site builder that may make tests a bit harder to follow.

Not an issue necessarily, and definitely not a blocker.

[kathmbeck]

I see what you're saying, I pulled this out because I had about ~200 lines of duplication. I could really go either way though -- happy to inline back if you think the consistency is more beneficial.

[eduardoboucas]

🚀