build: Migrate from Poetry to Setuptools in pyproject.toml (#158)

Author: plexoos

pyproject.toml

@@ -16,5 +16,8 @@ plot-csg = "optiphy.tools.plot_csg:main"
 serve-path = "optiphy.tools.serve_path:main"
 
 [build-system]
-requires = ["poetry-core"]
-build-backend = "poetry.core.masonry.api"
+requires = ["setuptools", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools]
+packages = ["optiphy"]