Add Introduced in label for new operators

Author: stefano-ottolenghi

modules/ROOT/pages/planning-and-tuning/operators/operators-detail.adoc

@@ -6005,6 +6005,7 @@ Total database accesses: 4, total allocated memory: 184
 
 ======
 
+[role=label--new-2025.11]
 [[query-plan-merge-into]]
 === Merge Into
 
@@ -6056,6 +6057,7 @@ Total database accesses: 15, total allocated memory: 2232
 
 ======
 
+[role=label--new-2025.11]
 [[query-plan-merge-unique-node]]
 === Merge Unique Node