add example usage

main.py

@@ -0,0 +1,15 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+from star_rail_relic_trimmer.load import show_relics_to_keep
+
+
+def main() -> None:
+    file = Path(__file__).parents[0] / "data.yaml"
+
+    show_relics_to_keep(file)
+
+
+if __name__ == "__main__":
+    main()