added CMake option `USE_INT128` and support built-in `__int128` / some compilation fixes#7840

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firewave wants to merge 3 commits intodanmar:mainfrom

Commits on Oct 21, 2025

added CMake option `USE_INT128` and support built-in `__int128` / some compilation fixes
firewave
committed
CI-unixish.yml: split some steps from `build_cmake`
firewave
committed
CI-unixish.yml: build with `USE_INT128` [skip ci]
firewave
committed