[clang] [BoundsSafety][Sema] Allow counted_by and counted_by_or_null on pointers where the pointee type is incomplete but potentially completable (PR #106321)

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https://github.com/Sirraide commented:

Alright, there are a few minor things I pointed out here, but nothing major. I think we should be able to land this soon barring any unforeseen complications ;Þ

https://github.com/llvm/llvm-project/pull/106321