Add dependencies and runtime setup documentation

src/taetigkeitsnachweis/cli.py

@@ -1 +1,34 @@
 """CLI entrypoint and orchestration layer."""
+
+from __future__ import annotations
+
+import argparse
+
+
+def build_parser() -> argparse.ArgumentParser:
+	parser = argparse.ArgumentParser(
+		prog="taetigkeitsnachweis",
+		description="SAB Taetigkeitsnachweise generator",
+	)
+	parser.add_argument(
+		"--version",
+		action="store_true",
+		help="Show tool version and exit.",
+	)
+	return parser
+
+
+def main() -> int:
+	parser = build_parser()
+	args = parser.parse_args()
+
+	if args.version:
+		print("taetigkeitsnachweis 0.1.0")
+		return 0
+
+	print("CLI scaffold ready. Full pipeline will be added in Task T13.")
+	return 0
+
+
+if __name__ == "__main__":
+	raise SystemExit(main())