Merge remote-tracking branch 'carlosdelest/non-issue/esql-knn-exact-search-non-pushed' into non-issue/esql-knn-exact-search-non-pushed

# Conflicts:
#	x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/querydsl/query/KnnQuery.java

Author: carlosdelest

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/vector/Knn.java

@@ -118,8 +118,8 @@ public Knn(
                     name = "min_candidates",
                     type = "integer",
                     valueHint = { "10" },
-                    description = "The minimum number of nearest neighbor candidates to consider per shard while doing knn search. " +
-                        " KNN may use a higher number of candidates in case the query can't use a approximate results. "
+                    description = "The minimum number of nearest neighbor candidates to consider per shard while doing knn search. "
+                        + " KNN may use a higher number of candidates in case the query can't use a approximate results. "
                         + "Cannot exceed 10,000. Increasing min_candidates tends to improve the accuracy of the final results. "
                         + "Defaults to 1.5 * LIMIT used for the query."
                 ),

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/optimizer/rules/logical/PushLimitToKnn.java

@@ -16,7 +16,6 @@
 import org.elasticsearch.xpack.esql.plan.logical.Limit;
 import org.elasticsearch.xpack.esql.plan.logical.LogicalPlan;
 import org.elasticsearch.xpack.esql.plan.logical.TopN;
-import org.elasticsearch.xpack.esql.plan.logical.UnaryPlan;
 import org.elasticsearch.xpack.esql.plan.logical.inference.Rerank;
 
 /**