Trying to hit the [execute API](https://www.elastic.co/guide/en/elasticsearch/painless/8.5/painless-execute-api.html) with an index that in available via cross cluster search will fail with an `IllegalArgumentException`: `Cross-cluster calls are not supported in this context but remote indices were requested`

That is because `PainlessExecuteAction`'s [`TransportAction`](https://github.com/elastic/elasticsearch/blob/8.5/modules/lang-painless/src/main/java/org/elasticsearch/painless/action/PainlessExecuteAction.java#L462) is a [`TransportSingleShardAction`](https://github.com/elastic/elasticsearch/blob/8.5/server/src/main/java/org/elasticsearch/action/support/single/shard/TransportSingleShardAction.java#L153) which uses [`IndexNameExpressionResolver.concreteIndices`](https://github.com/elastic/elasticsearch/blob/8.5/server/src/main/java/org/elasticsearch/cluster/metadata/IndexNameExpressionResolver.java#L331), which does not support remote clusters.

What would it take it enable PainlessExecuteAction to support CCS?

Kibana uses the execute api to validate runtime fields on edit, see https://github.com/elastic/kibana/issues/145861
modules/lang-painless/src/main/java/org/elasticsearch/painless/action/PainlessExecuteAction.java
import org.elasticsearch.index.mapper.OnScriptError;
import org.elasticsearch.index.mapper.ParsedDocument;
import org.elasticsearch.index.mapper.SourceToParse;
import org.elasticsearch.index.query.AbstractQueryBuilder;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.SearchExecutionContext;
import org.elasticsearch.index.shard.ShardId;
import org.elasticsearch.indices.IndicesService;
import org.elasticsearch.painless.spi.PainlessTestScript;
import org.elasticsearch.rest.BaseRestHandler;
import org.elasticsearch.rest.RestRequest;
import org.elasticsearch.rest.Scope;
import org.elasticsearch.rest.ServerlessScope;
import org.elasticsearch.rest.action.RestToXContentListener;
import org.elasticsearch.script.BooleanFieldScript;
import org.elasticsearch.script.CompositeFieldScript;
import org.elasticsearch.script.DateFieldScript;
import org.elasticsearch.script.DocValuesDocReader;
import org.elasticsearch.script.DoubleFieldScript;
import org.elasticsearch.script.FilterScript;
import org.elasticsearch.script.GeoPointFieldScript;
import org.elasticsearch.script.IpFieldScript;
import org.elasticsearch.script.LongFieldScript;
import org.elasticsearch.script.ScoreScript;
import org.elasticsearch.script.Script;
import org.elasticsearch.script.ScriptContext;
import org.elasticsearch.script.ScriptModule;
import org.elasticsearch.script.ScriptService;
import org.elasticsearch.script.ScriptType;
import org.elasticsearch.script.StringFieldScript;