adding to changelog

Author: ihrpr

docs/specification/draft/changelog.mdx

@@ -7,7 +7,9 @@ the previous revision, [2025-03-26](/specification/2025-03-26).
 
 ## Major changes
 
-1. TODO
+1. Removed support for JSON-RPC **[batching](https://www.jsonrpc.org/specification#batch)**
+   (PR [#416](https://github.com/modelcontextprotocol/specification/pull/416)) 
+2. TODO
 
 ## Other schema changes