Add pyproject.toml to define build system requirements

Specifies setuptools as the build backend and ensures that Cython, numpy, and wheel are available as build-time dependencies to support modern PEP 517 build workflows.

This allows `pip install -e .`

Author: calvinp0

pyproject.toml

@@ -0,0 +1,8 @@
+[build-system]
+requires = [
+    "setuptools>=64",
+    "wheel",
+    "Cython",
+    "numpy",
+]
+build-backend = "setuptools.build_meta"