update+fix Cython / ci-buildwheels

[pp-mo]

Effectively, a placeholder for a bunch of tasks

Tasks

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1. Error building from source #389
   New: Issue Type: Bug Type: Infrastructure community +4
   
2. cf-units doesn't install with pip on Python 3.12.3 #432
   New: Issue Type: Bug Type: Infrastructure community +4
   
3. cf_units not working on macOS arm64 #438
   New: Issue Type: Bug Type: Infrastructure community +4
4. Release a macos 14 compatible release. #413
   New: Feature Type: Infrastructure community +3
   
5. cf-units wheel on pypi not compatible with numpy2 #443
   New: Issue Type: Bug Type: Infrastructure community +4

NOTE: I've relegated all those individual tasks from "Backlog" to "No Status" on the board
This simplifies the board, and I think they are probably cross-coupled (fixing one may fix others)
So.. I think we first fix the basic build + then see what else still needs doing