Update README.md before archiving (#633)
diff --git a/README.md b/README.md
index b1c8695..3888b68 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,6 @@
+> [!IMPORTANT]
+> This repo has moved to https://github.com/dart-lang/tools/tree/main/pkgs/markdown
+
[](https://github.com/dart-lang/markdown/actions?query=workflow%3A"Dart+CI"+branch%3Amaster)
[](https://pub.dev/packages/markdown)
[](https://pub.dev/packages/markdown/publisher)