Improve changelog

CHANGELOG.md

@@ -11,8 +11,11 @@ changes.
 
 ## [0.17.0] - UNRELEASED
 
-- **BREAKING** `hydra-node` `/commit` enpoint now also accepts a _blueprint_
-  transaction together with the `UTxO` used to resolve the transaction inputs.
+- **BREAKING** `hydra-node` `/commit` enpoint now also accepts a _blueprint/draft_
+  transaction together with the `UTxO` which is spent in this transaction. `hydra-node` can
+  still be used like before if the provided `UTxO` is at public key address. In order to spend
+  from a script `UTxO`, and also unlock more involved use-cases, users need to provide additional
+  unsigned transaction that correctly specifies required data (like redeemers, validity ranges etc.)
 
 ## [0.16.0] - 2024-04-03