chore: update development status to stable for v1.0.0

Update PyPI classifier from Beta to Production/Stable as we prepare
for the first stable release.

pyproject.toml

@@ -25,7 +25,7 @@ keywords = [
     "dead-code"
 ]
 classifiers = [
-    "Development Status :: 4 - Beta",
+    "Development Status :: 5 - Production/Stable",
     "Environment :: Console",
     "Intended Audience :: Developers",
     "License :: OSI Approved :: MIT License",