Simplify KILL QUERY settings to always use empty QuerySettings

Use a fresh QuerySettings instance instead of copying default settings
and removing session-related ones. This is simpler, more stable, and
KILL QUERY doesn't need any special settings to execute.

Agent-Logs-Url: https://github.com/ClickHouse/clickhouse-java/sessions/46c2fb43-ed16-4140-82e1-e9ecacc80711

Co-authored-by: chernser <827456+chernser@users.noreply.github.com>

Author: Claude

jdbc-v2/src/main/java/com/clickhouse/jdbc/StatementImpl.java

@@ -337,15 +337,9 @@ public void cancel() throws SQLException {
             + (connection.onCluster ? "ON CLUSTER " + connection.cluster + " " : "")
             + "WHERE query_id = '" + lastQueryId + "'";
 
-        // Create query settings without session to avoid "Session is locked by a concurrent client" error
-        QuerySettings killQuerySettings = new QuerySettings();
-        if (connection.getDefaultQuerySettings() != null) {
-            killQuerySettings.getAllSettings().putAll(connection.getDefaultQuerySettings().getAllSettings());
-        }
-        killQuerySettings.setSessionId(null);
-        killQuerySettings.setSessionCheck(false);
-
-        try (QueryResponse response = connection.getClient().query(sql, killQuerySettings).get()){
+        // Use empty QuerySettings to avoid "Session is locked by a concurrent client" error
+        // KILL QUERY doesn't need any special settings and should execute without session context
+        try (QueryResponse response = connection.getClient().query(sql, new QuerySettings()).get()){
             LOG.debug("Query {} was killed by {}", lastQueryId, response.getQueryId());
         } catch (Exception e) {
             throw new SQLException(e);