test(unit): add ContentMoveOperationService interface contract tests

Verifies interface exists, extends IService, and has all required methods.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/Umbraco.Tests.UnitTests/Umbraco.Core/Services/ContentMoveOperationServiceInterfaceTests.cs

@@ -0,0 +1,72 @@
+using System.Reflection;
+using NUnit.Framework;
+using Umbraco.Cms.Core.Models;
+using Umbraco.Cms.Core.Services;
+
+namespace Umbraco.Cms.Tests.UnitTests.Umbraco.Core.Services;
+
+[TestFixture]
+public class ContentMoveOperationServiceInterfaceTests
+{
+    [Test]
+    public void Interface_Exists_And_Is_Public()
+    {
+        var interfaceType = typeof(IContentMoveOperationService);
+
+        Assert.That(interfaceType, Is.Not.Null);
+        Assert.That(interfaceType.IsInterface, Is.True);
+        Assert.That(interfaceType.IsPublic, Is.True);
+    }
+
+    [Test]
+    public void Interface_Extends_IService()
+    {
+        var interfaceType = typeof(IContentMoveOperationService);
+
+        Assert.That(typeof(IService).IsAssignableFrom(interfaceType), Is.True);
+    }
+
+    [Test]
+    [TestCase("Move", new[] { typeof(IContent), typeof(int), typeof(int) })]
+    [TestCase("EmptyRecycleBin", new[] { typeof(int) })]
+    [TestCase("RecycleBinSmells", new Type[] { })]
+    [TestCase("Copy", new[] { typeof(IContent), typeof(int), typeof(bool), typeof(int) })]
+    [TestCase("Copy", new[] { typeof(IContent), typeof(int), typeof(bool), typeof(bool), typeof(int) })]
+    public void Interface_Has_Required_Method(string methodName, Type[] parameterTypes)
+    {
+        var interfaceType = typeof(IContentMoveOperationService);
+        var method = interfaceType.GetMethod(methodName, parameterTypes);
+
+        Assert.That(method, Is.Not.Null, $"Method {methodName} should exist with specified parameters");
+    }
+
+    [Test]
+    public void Interface_Has_Sort_Methods()
+    {
+        var interfaceType = typeof(IContentMoveOperationService);
+
+        // Sort with IEnumerable<IContent>
+        var sortContentMethod = interfaceType.GetMethods()
+            .FirstOrDefault(m => m.Name == "Sort" &&
+                m.GetParameters().Length == 2 &&
+                m.GetParameters()[0].ParameterType.IsGenericType);
+
+        // Sort with IEnumerable<int>
+        var sortIdsMethod = interfaceType.GetMethods()
+            .FirstOrDefault(m => m.Name == "Sort" &&
+                m.GetParameters().Length == 2 &&
+                m.GetParameters()[0].ParameterType == typeof(IEnumerable<int>));
+
+        Assert.That(sortContentMethod, Is.Not.Null, "Sort(IEnumerable<IContent>, int) should exist");
+        Assert.That(sortIdsMethod, Is.Not.Null, "Sort(IEnumerable<int>, int) should exist");
+    }
+
+    [Test]
+    public void Implementation_Inherits_ContentServiceBase()
+    {
+        var implementationType = typeof(ContentMoveOperationService);
+        var baseType = typeof(ContentServiceBase);
+
+        Assert.That(baseType.IsAssignableFrom(implementationType), Is.True);
+    }
+}