[test](catalog) Add unit tests for Replica schemaHash polymorphism

Add four tests to ReplicaTest covering the schemaHash behavior change:
- testLocalReplicaGetSchemaHash: constructor value is returned
- testLocalReplicaSetSchemaHash: setter updates the value
- testBaseReplicaSchemaHashReturnsNegativeOne: base class returns -1, setter is no-op
- testCloudReplicaSchemaHashReturnsNegativeOne: CloudReplica inherits -1 stub

Generated by ThinkOps

Author: dataroaring

fe/fe-core/src/test/java/org/apache/doris/catalog/ReplicaTest.java

@@ -18,6 +18,7 @@
 package org.apache.doris.catalog;
 
 import org.apache.doris.catalog.Replica.ReplicaState;
+import org.apache.doris.cloud.catalog.CloudReplica;
 import org.apache.doris.common.io.Text;
 import org.apache.doris.persist.gson.GsonUtils;
 
@@ -195,4 +196,41 @@ public void testUpdateVersion3() {
         Assert.assertEquals(18, originalReplica.getVersion());
         Assert.assertEquals(-1, originalReplica.getLastFailedVersion());
     }
+
+    @Test
+    public void testLocalReplicaGetSchemaHash() {
+        int schemaHash = 12345;
+        LocalReplica localReplica = new LocalReplica(10000, 20000, 3, schemaHash,
+                100, 0, 78, ReplicaState.NORMAL, 0, 3);
+        Assert.assertEquals(schemaHash, localReplica.getSchemaHash());
+    }
+
+    @Test
+    public void testLocalReplicaSetSchemaHash() {
+        LocalReplica localReplica = new LocalReplica(10000, 20000, 3, 111,
+                100, 0, 78, ReplicaState.NORMAL, 0, 3);
+        Assert.assertEquals(111, localReplica.getSchemaHash());
+        localReplica.setSchemaHash(222);
+        Assert.assertEquals(222, localReplica.getSchemaHash());
+    }
+
+    @Test
+    public void testBaseReplicaSchemaHashReturnsNegativeOne() {
+        // Base Replica (and by extension CloudReplica) should return -1 for schemaHash
+        // since schemaHash is only meaningful for LocalReplica
+        Replica baseReplica = new Replica();
+        Assert.assertEquals(-1, baseReplica.getSchemaHash());
+
+        // setSchemaHash is a no-op on base Replica
+        baseReplica.setSchemaHash(999);
+        Assert.assertEquals(-1, baseReplica.getSchemaHash());
+    }
+
+    @Test
+    public void testCloudReplicaSchemaHashReturnsNegativeOne() {
+        // CloudReplica extends Replica (not LocalReplica), so it inherits the -1 stub
+        CloudReplica cloudReplica = new CloudReplica(10000L, 20000L, ReplicaState.NORMAL,
+                3, 12345, 1, 2, 3, 4, -1);
+        Assert.assertEquals(-1, cloudReplica.getSchemaHash());
+    }
 }