Add a page size system feature

[RossComputerGuy]

Is your feature request related to a problem?

Many derivations don't build with a non-standard page size (> 4k).

Proposed solution

Add a set of system features which are added in based on the page sizes the system supports.

Alternative solutions

• Mark packages as broken on possible architectures.
• Don't use a non-standard page size (decreases performance or not possible on some systems ie Asahi)
• Fix packages (some may refuse to like jemalloc)

Additional context

Page size refers to the size of an individual page of memory.

Checklist

• checked latest Nix manual (source)
• checked open feature issues and pull requests for possible duplicates

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[RossComputerGuy]

I came up with #12446 which implements the feature which is based on Zix's reference implementation at: RossComputerGuy/zix#26