test: add LookupApiClientIntegrationTests for lookup endpoint validation

Add 4 integration tests for LookupApiClient that verify lookup endpoints
work correctly through the actual HTTP pipeline without authentication.

NEW/tests/JdeScoping.Api.IntegrationTests/ClientIntegration/LookupApiClientIntegrationTests.cs

@@ -0,0 +1,53 @@
+using JdeScoping.Client.Services;
+using Shouldly;
+
+namespace JdeScoping.Api.IntegrationTests.ClientIntegration;
+
+public class LookupApiClientIntegrationTests : ClientIntegrationTestBase
+{
+    public LookupApiClientIntegrationTests(TestWebApplicationFactory factory) : base(factory) { }
+
+    [Fact]
+    public async Task FindItemsAsync_WithoutAuth_ReturnsSuccess()
+    {
+        // Lookup endpoints don't require auth
+        var freshClient = new LookupApiClient(CreateFreshClient());
+
+        // Act
+        var result = await freshClient.FindItemsAsync("test");
+
+        // Assert
+        result.IsSuccess.ShouldBeTrue();
+        result.Value.ShouldNotBeNull();
+    }
+
+    [Fact]
+    public async Task FindProfitCentersAsync_ReturnsSuccess()
+    {
+        // Act
+        var result = await LookupClient.FindProfitCentersAsync("test");
+
+        // Assert
+        result.IsSuccess.ShouldBeTrue();
+    }
+
+    [Fact]
+    public async Task FindWorkCentersAsync_ReturnsSuccess()
+    {
+        // Act
+        var result = await LookupClient.FindWorkCentersAsync("test");
+
+        // Assert
+        result.IsSuccess.ShouldBeTrue();
+    }
+
+    [Fact]
+    public async Task FindOperatorsAsync_ReturnsSuccess()
+    {
+        // Act
+        var result = await LookupClient.FindOperatorsAsync("test");
+
+        // Assert
+        result.IsSuccess.ShouldBeTrue();
+    }
+}