[Kernel][Clustering #3] add ClusteringMetadataDomain (delta-io#4321)

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## Description

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Split the main PR delta-io#4265 for faster
review

add `ClusteringMetadataDomain` which could generate the clustering
domain metadata like
```
{
  "domainMetadata": {
    "domain": "delta.clustering",
    "configuration": "{\"clusteringColumns\":[\"col-daadafd7-7c20-4697-98f8-bff70199b1f9\", \"col-5abe0e80-cf57-47ac-9ffc-a861a3d1077e\"]}",
    "removed": false
  }
}
```
## How was this patch tested?

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unit tests
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Author: KaiqiJinWow

kernel/kernel-api/src/main/java/io/delta/kernel/internal/clustering/ClusteringMetadataDomain.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright (2025) The Delta Lake Project Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.delta.kernel.internal.clustering;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import io.delta.kernel.expressions.Column;
+import io.delta.kernel.internal.SnapshotImpl;
+import io.delta.kernel.internal.metadatadomain.JsonMetadataDomain;
+import java.util.*;
+import java.util.stream.Collectors;
+
+/** Represents the metadata domain for clustering. */
+public final class ClusteringMetadataDomain extends JsonMetadataDomain {
+
+  public static final String DOMAIN_NAME = "delta.clustering";
+
+  /**
+   * Constructs a ClusteringMetadataDomain with the clustering columns.
+   *
+   * @param clusteringColumns the columns used for clustering. If column mapping is enabled, use the
+   *     physical name assigned; otherwise, use the logical column name.
+   */
+  public static ClusteringMetadataDomain fromClusteringColumns(List<Column> clusteringColumns) {
+    return new ClusteringMetadataDomain(
+        clusteringColumns.stream()
+            .map(column -> Arrays.asList(column.getNames()))
+            .collect(Collectors.toList()));
+  }
+
+  /**
+   * Creates an instance of {@link ClusteringMetadataDomain} from a JSON configuration string.
+   *
+   * @param json the JSON configuration string
+   */
+  public static ClusteringMetadataDomain fromJsonConfiguration(String json) {
+    return JsonMetadataDomain.fromJsonConfiguration(json, ClusteringMetadataDomain.class);
+  }
+
+  /**
+   * Creates an optional instance of {@link ClusteringMetadataDomain} from a {@link SnapshotImpl} if
+   * present.
+   *
+   * @param snapshot the snapshot instance
+   */
+  // TODO: Add the test coverage for this function in the integration test.
+  public static Optional<ClusteringMetadataDomain> fromSnapshot(SnapshotImpl snapshot) {
+    return JsonMetadataDomain.fromSnapshot(snapshot, ClusteringMetadataDomain.class, DOMAIN_NAME);
+  }
+
+  /**
+   * The column names used for clustering. If column mapping is enabled, we use physical column
+   * names, otherwise we would store its logical column names. Stored as a List of Lists to avoid
+   * customized serialization and deserialization logic.
+   */
+  @JsonProperty("clusteringColumns")
+  private final List<List<String>> clusteringColumns;
+
+  @JsonCreator
+  private ClusteringMetadataDomain(
+      @JsonProperty("clusteringColumns") List<List<String>> physicalClusteringColumns) {
+    this.clusteringColumns = physicalClusteringColumns;
+  }
+
+  @Override
+  public String getDomainName() {
+    return DOMAIN_NAME;
+  }
+
+  @JsonIgnore
+  public List<Column> getClusteringColumns() {
+    return clusteringColumns.stream()
+        .map(list -> new Column(list.toArray(new String[0])))
+        .collect(Collectors.toList());
+  }
+}

kernel/kernel-api/src/test/scala/io/delta/kernel/internal/clustering/ClusteringMetadataDomainSuite.scala

@@ -0,0 +1,104 @@
+/*
+ * Copyright (2025) The Delta Lake Project Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.delta.kernel.internal.clustering
+
+import scala.collection.JavaConverters._
+
+import io.delta.kernel.expressions.Column
+import io.delta.kernel.internal.util.{ColumnMapping, ColumnMappingSuiteBase}
+import io.delta.kernel.types._
+
+import org.scalatest.funsuite.AnyFunSuite
+
+class ClusteringMetadataDomainSuite
+    extends AnyFunSuite
+    with ColumnMappingSuiteBase {
+
+  private def convertToPhysicalColumn(
+      logicalColumns: List[Column],
+      schema: StructType): List[Column] = {
+    logicalColumns.map { column =>
+      ColumnMapping.getPhysicalColumnNameAndDataType(schema, column)._1
+    }
+  }
+
+  test("ClusteringDomainMetadata can be serialized") {
+    val clusteringColumns =
+      List(new Column(Array("col1", "`col2,col3`", "`col4.col5`,col6")))
+    val clusteringMetadataDomain = ClusteringMetadataDomain.fromClusteringColumns(
+      clusteringColumns.asJava)
+    val serializedString = clusteringMetadataDomain.toDomainMetadata.toString
+    assert(serializedString ===
+      """|DomainMetadata{domain='delta.clustering', configuration=
+         |'{"clusteringColumns":[["col1","`col2,col3`","`col4.col5`,col6"]]}',
+         | removed='false'}""".stripMargin.replace("\n", ""))
+  }
+
+  test("ClusteringDomainMetadata can be deserialized") {
+    val configJson = """{"clusteringColumns":[["col1","`col2,col3`","`col4.col5`,col6"]]}"""
+    val clusteringMD = ClusteringMetadataDomain.fromJsonConfiguration(configJson)
+
+    assert(clusteringMD.getClusteringColumns === List(new Column(Array(
+      "col1",
+      "`col2,col3`",
+      "`col4.col5`,col6"))).asJava)
+  }
+
+  test("Successfully get DomainMetadata for non-nested columns") {
+    val schema = new StructType()
+      .add("id", IntegerType.INTEGER, true)
+      .add("name", IntegerType.INTEGER, true)
+      .add("age", IntegerType.INTEGER, true)
+
+    val clusterColumns = List(new Column("name"), new Column("age"))
+    val physicalColumns = convertToPhysicalColumn(clusterColumns, schema)
+
+    val clusteringMetadataDomain =
+      ClusteringMetadataDomain.fromClusteringColumns(
+        physicalColumns.asJava)
+
+    val clusteringDomainMetadata = clusteringMetadataDomain.toDomainMetadata
+    assert(clusteringMetadataDomain.getClusteringColumns == clusterColumns.asJava)
+    assert(clusteringDomainMetadata.getDomain == "delta.clustering")
+    assert(clusteringDomainMetadata.getConfiguration ==
+      """{"clusteringColumns":[["name"],["age"]]}""")
+  }
+
+  test("Successfully get DomainMetadata for nested columns") {
+    val schema = new StructType()
+      .add("id", IntegerType.INTEGER, true)
+      .add(
+        "user",
+        new StructType()
+          .add(
+            "address",
+            new StructType()
+              .add("city", StringType.STRING, true)))
+
+    val clusterColumns = List(new Column(Array("user", "address", "city")))
+    val physicalColumns = convertToPhysicalColumn(clusterColumns, schema)
+
+    val clusteringMetadataDomain = ClusteringMetadataDomain.fromClusteringColumns(
+      physicalColumns.asJava)
+
+    val clusteringDomainMetadata = clusteringMetadataDomain.toDomainMetadata
+    assert(clusteringMetadataDomain.getClusteringColumns ==
+      List(new Column(Array("user", "address", "city"))).asJava)
+    assert(clusteringDomainMetadata.getDomain == "delta.clustering")
+    assert(clusteringDomainMetadata.getConfiguration ==
+      """{"clusteringColumns":[["user","address","city"]]}""")
+  }
+}