Clarify the pipeline snapshot workflow

README.md

@@ -49,8 +49,9 @@ The collection source exposes a reviewed snapshot of this role as
 Collection consumers should follow the unified bootstrap instructions in the
 [`rakestraw.dnd` collection repository](https://gitea.maximumdirect.net/eric/ansible-collection-dnd).
 This standalone repository remains authoritative for role changes; collection
-maintainers import a reviewed release as a snapshot. Collection releases are
-published independently and are listed in the collection repository.
+maintainers import a reviewed, pushed commit or immutable tag as a snapshot.
+Collection releases are published independently and are listed in the
+collection repository.
 
 ## Variables