mention migration guide in datacrunch package README.md

Author: shamrin

datacrunch_compat/README.md

@@ -1,5 +1,7 @@
 # datacrunch is now verda
 
-This package has been [renamed](https://verda.com/blog/datacrunch-is-changing-its-name-to-verda). Use `pip install verda` or `uv add verda` instead.
+This package has been renamed to `verda`. Use `pip install verda` or `uv add verda` instead.
+
+To migrate from `datacrunch`, follow [the migration guide](https://github.com/verda-cloud/sdk-python/blob/master/MIGRATION.md).
 
 New package: https://pypi.org/project/verda/