internal: refactor for packaging

Package using python-build, python-installer and hatch

src/caelestia/__init__.py

@@ -0,0 +1,9 @@
+from caelestia.parser import parse_args
+
+
+def main() -> None:
+    args = parse_args()
+    args.cls(args).run()
+
+if __name__ == "__main__":
+    main()