Add possibly missing headers

As observed in #317 with some change, we got an error about missing headers: https://github.com/Algebraic-Programming/ALP/actions/runs/19696257418/job/56421790501
This means that some headers should be added (for example `#include <cstdint>` in files using `uintptr_t`)

Surely there are other instances of such cases that can be added to the issue