Update README.md

Jameswlepage · web-flow · commit 4dd7d5ca45c2 · 2025-07-18T10:07:06.000-04:00
diff --git a/README.md b/README.md
@@ -32,4 +32,4 @@
 * **Prototype:** experiment with the upcoming Composer package once released.
 
 ## License
-GPL-3
+[GPL-2.0-or-later](https://spdx.org/licenses/GPL-2.0-or-later.html)
