Move to a specialized heap allocation function

[vabold]

This has historically caused problems when attempting to bring an API to a higher language. Example:

$ python
Python 3.12.7 (main, Oct  1 2024, 11:15:50) [GCC 14.2.1 20240910] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import pynoko
[Heap.cc:139] WARN: HEAP ALLOC FAIL: Cannot allocate 8 from heap (nil)

zsh: segmentation fault (core dumped)  python

Rather than hide the visibility of our overloaded operator new (which is a known GCC bug that requires hacky workarounds), we should instead provide a way for developers to opt out.

[vabold]

Changed to reflect a more practical solution.