feat: add runner program entry file.
diff --git a/src/main.py b/src/main.py
new file mode 100644
index 0000000..e6d098d
--- /dev/null
+++ b/src/main.py
@@ -0,0 +1,6 @@
+def main() -> None:
+    pass
+
+
+if __name__ == '__main__':
+    main()