comment out session clearing step in SessionStateMiddleware

Author: ncapek

src/keboola_mcp_server/mcp.py

@@ -161,7 +161,9 @@ async def on_message(
         try:
             return await call_next(context)
         finally:
-            ctx.session.state = {}
+            # NOTE: This line is commented following a bug related to session state clearance in Claude client
+            # ctx.session.state = {}
+            pass
 
     @staticmethod
     def _create_session_state(config: Config) -> dict[str, Any]: