Permit `ARR_WORDS` closures outside `HEAP_ALLOCED` space

This is a rebase of !2561 on master.

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Motivation for this change

We would like to be able to have byte arrays that live off the garbage collector managed heap. Therefore we allow ARR_WORDS closure outside the HEAP_ALLOCED space. We also need to be able to write the ByteArray# header in front of the data, in order to write this C struct we added the placeByteArray# primop.

• The specific issue that this addresses is #17747
• The specific branch that this merge request revived is !2561
• This merge request is part of the GHC workshop of 2023 and was finished during ZuriHac 2024.