ci: Get closer to cross-compile darwin-x64 on darwin-aarch64

[Electroid]

What does this PR do?

This does not enable cross-complication. However, it fixes various CI things.

• Documentation or TypeScript types (it's okay to leave the rest blank in this case)
• Code changes

How did you verify your code works?

[robobun]

^{Updated 6:34 PM PT - Dec 20th, 2024}

✅ @Electroid, your commit 0d34fae has passed in #8373! 🎉

---

🧪   try this PR locally:

bunx bun-pr 15918

[Jarred-Sumner]

The diff removing usages of the CPU macro is a CI configuration issue. Many more things will break if the CPU() macro is not working correctly. The code will likely not load at runtime