KAFKA-18780: Extend RetriableException related exceptions (#19020)

- Added a unit test to validate the exception hierarchy for all KIP-1050
transaction related exceptions.
- RetriableException is correctly extended by all child classes
- Included test for RetriableException exception with verification that
all exceptions extending `RetriableException` do not inadvertently
extend `RefreshRetriableException, preserving the intended behavior.

Reviewers: Kirk True <ktrue@confluent.io>, TaiJuWu <tjwu1217@gmail.com>, TengYao Chi <kitingiao@gmail.com>,  Ken Huang <s7133700@gmail.com>, Justine Olshan <jolshan@confluent.io>

clients/src/test/java/org/apache/kafka/common/errors/TransactionExceptionHierarchyTest.java

@@ -0,0 +1,51 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 org.apache.kafka.common.errors;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class TransactionExceptionHierarchyTest {
+
+    /**
+     * Verifies that the given exception class extends `RetriableException`
+     * and does **not** extend `RefreshRetriableException`.
+     *
+     * Using `RefreshRetriableException` changes the exception handling behavior,
+     * so only exceptions extending `RetriableException` directly are considered valid here.
+     *
+     * @param exceptionClass the exception class to check
+     */
+    @ParameterizedTest
+    @ValueSource(classes = {
+        TimeoutException.class,
+        NotEnoughReplicasException.class,
+        CoordinatorLoadInProgressException.class,
+        CorruptRecordException.class,
+        NotEnoughReplicasAfterAppendException.class,
+        ConcurrentTransactionsException.class
+    })
+    void testRetriableExceptionHierarchy(Class<? extends Exception> exceptionClass) {
+        assertTrue(RetriableException.class.isAssignableFrom(exceptionClass),
+                exceptionClass.getSimpleName() + " should extend RetriableException");
+        assertFalse(RefreshRetriableException.class.isAssignableFrom(exceptionClass),
+                exceptionClass.getSimpleName() + " should NOT extend RefreshRetriableException");
+    }
+}