ESQL: INLINESTATS implementation with multiple LogicalPlan updates (#128917)

Part of #124715 and
similar to #128476.
Different from #128476 in
that it takes a "LogicalPlan" approach to running a sub-query,
integrating its result back in the "main" LogicalPlan and continuing
running the query.

Author: astefan

docs/changelog/128917.yaml

@@ -0,0 +1,6 @@
+pr: 128917
+summary: Adopt a "LogicalPlan" approach to running multiple sub-queries (with INLINESTATS
+  so far)
+area: ES|QL
+type: enhancement
+issues: []

server/src/main/java/org/elasticsearch/TransportVersions.java

@@ -333,6 +333,7 @@ static TransportVersion def(int id) {
     public static final TransportVersion ESQL_SERIALIZE_TIMESERIES_FIELD_TYPE = def(9_114_0_00);
     public static final TransportVersion ML_INFERENCE_IBM_WATSONX_COMPLETION_ADDED = def(9_115_0_00);
     public static final TransportVersion ESQL_SPLIT_ON_BIG_VALUES = def(9_116_0_00);
+    public static final TransportVersion ESQL_LOCAL_RELATION_WITH_NEW_BLOCKS = def(9_117_0_00);
 
     /*
      * STOP! READ THIS FIRST! No, really,

x-pack/plugin/esql/qa/server/multi-clusters/src/javaRestTest/java/org/elasticsearch/xpack/esql/ccq/MultiClusterSpecIT.java

@@ -49,7 +49,7 @@
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.FORK_V9;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.INLINESTATS;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.INLINESTATS_V2;
-import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.INLINESTATS_V7;
+import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.INLINESTATS_V8;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_LOOKUP_V12;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.JOIN_PLANNING_V1;
 import static org.elasticsearch.xpack.esql.action.EsqlCapabilities.Cap.METADATA_FIELDS_REMOTE_TEST;
@@ -128,7 +128,7 @@ protected void shouldSkipTest(String testName) throws IOException {
         assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(INLINESTATS.capabilityName()));
         assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(INLINESTATS_V2.capabilityName()));
         assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(JOIN_PLANNING_V1.capabilityName()));
-        assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(INLINESTATS_V7.capabilityName()));
+        assumeFalse("INLINESTATS not yet supported in CCS", testCase.requiredCapabilities.contains(INLINESTATS_V8.capabilityName()));
         assumeFalse("LOOKUP JOIN not yet supported in CCS", testCase.requiredCapabilities.contains(JOIN_LOOKUP_V12.capabilityName()));
         // Unmapped fields require a coorect capability response from every cluster, which isn't currently implemented.
         assumeFalse("UNMAPPED FIELDS not yet supported in CCS", testCase.requiredCapabilities.contains(UNMAPPED_FIELDS.capabilityName()));

x-pack/plugin/esql/qa/testFixtures/src/main/java/org/elasticsearch/xpack/esql/EsqlTestUtils.java

@@ -83,6 +83,7 @@
 import org.elasticsearch.xpack.esql.plan.logical.EsRelation;
 import org.elasticsearch.xpack.esql.plan.logical.Limit;
 import org.elasticsearch.xpack.esql.plan.logical.LogicalPlan;
+import org.elasticsearch.xpack.esql.plan.logical.local.EmptyLocalSupplier;
 import org.elasticsearch.xpack.esql.plan.logical.local.LocalRelation;
 import org.elasticsearch.xpack.esql.plan.logical.local.LocalSupplier;
 import org.elasticsearch.xpack.esql.plugin.EsqlPlugin;
@@ -446,7 +447,7 @@ public static Literal L(Object value) {
     }
 
     public static LogicalPlan emptySource() {
-        return new LocalRelation(Source.EMPTY, emptyList(), LocalSupplier.EMPTY);
+        return new LocalRelation(Source.EMPTY, emptyList(), EmptyLocalSupplier.EMPTY);
     }
 
     public static LogicalPlan localSource(BlockFactory blockFactory, List<Attribute> fields, List<Object> row) {