Maybe doing TDD, where a human engineer writes the test and asks the AI agent to write the code to make it pass?
I haven't yet tried vibe coding to be honest but TDD, I do very often and it's a good way to control how the code grows, among other things.

Apple put together their own hardware so it's easier for them to make their software compatible. Almost other laptop makers invest in making their hardware compatible with Windows. In the case of Linux, the community strives to keep up with hardware advancement.

Once the code freeze is lifted all the team have to do is merge that branch to main. Of course, this implies that the same checks that run for your main branch are run in this other branch

I agree with what others have said that there's a difference between code freeze and release freeze but if you are stuck with the former what have worked for teams I have been in the past is to have a branch to integrate all PRs