fix: resolve test collection failure in CI

- Add explicit setuptools configuration for src layout
- Remove old nutrient.egg-info directory artifacts
- Clean up debug test files
- This fixes the pytest exit code 2 issue by ensuring the package
  is properly discovered and installed in the CI environment

Author: jdrhyne

pyproject.toml

@@ -2,6 +2,12 @@
 requires = ["setuptools>=61.0", "wheel"]
 build-backend = "setuptools.build_meta"
 
+[tool.setuptools]
+package-dir = {"" = "src"}
+
+[tool.setuptools.packages.find]
+where = ["src"]
+
 [project]
 name = "nutrient-dws"
 version = "1.0.0"