PumpDeviceIntegrationServer - Register DeviceHealth node, use HasAddIn for SoftwareUpdate (#4008)

This pull request makes important improvements to how the
`SoftwareUpdate` object is modeled and registered in the OPC UA Device
Integration (DI) server, ensuring better compliance with the OPC
10000-100 specification and improved compatibility with companion-spec
checkers. The main changes involve updating the reference type for
`SoftwareUpdate` to use `HasAddIn`, explicitly registering the
`DeviceHealth` node, and enhancing related tests.

**Device Model Compliance and Registration:**

* The `SoftwareUpdate` object is now attached to its host device using
the `HasAddIn` reference type instead of `HasComponent`, aligning with
the OPC 10000-100 specification and reducing validation noise from
companion-spec checkers.
* The `DeviceHealth` child node is now explicitly registered with the
node manager after device registration to ensure its attributes resolve
correctly and it can be mapped by companion-spec checkers.

**Testing Improvements:**

* Added a test assertion to verify that the `SoftwareUpdate` child is
attached via the `HasAddIn` reference, ensuring the implementation
matches the OPC UA specification.Explicitly register DeviceHealth child
node after creation to ensure attributes resolve and DI checker
compatibility. Reference SoftwareUpdate facet via HasAddIn per OPC
10000-100 spec, not HasComponent, to avoid validation issues. Update
tests to assert correct reference type.

# Description

_Describe the changes here to communicate to the maintainers why they
should accept this pull request. By default - this will become the
Commit message after merging and thus define history._

## Related Issues

_Reference all GitHub issues this PR addresses. If there is no issue
yet, open one and link it here._

_If this is a relatively large or complex change, a design must have
been discussed in the related tracking issue and signed off (which
becomes the Architectural Decision Record (ADR))._

- Fixes #github-issue-number, ...

## Checklist

_Put an `x` in the boxes that apply. You can complete these step by step
after opening the PR._

- [ ] I have signed the
[CLA](https://opcfoundation.org/license/cla/ContributorLicenseAgreementv1.0.pdf)
and read the
[CONTRIBUTING](https://github.com/OPCFoundation/UA-.NETStandard/blob/master/CONTRIBUTING.md)
doc.
- [ ] I have added tests that prove my fix is effective or that my
feature works and increased code coverage.
- [ ] I have added all necessary documentation.
- [ ] I have verified that my changes do not introduce (new) build or
analyzer warnings.
- [ ] I ran **all** tests locally using the **UA.slnx** solution against
at least .net **framework** and .net **10**, and all passed.
- [ ] I fixed **all** failing and flaky tests in the CI pipelines and
**all** CodeQL warnings.
- [ ] I have addressed **all** PR feedback received.

---------

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: koepalex

Applications/PumpDeviceIntegrationServer/Program.cs

@@ -94,6 +94,16 @@
         // the simulated supervision flags shared across both pumps).
         pump.Device.AddDeviceHealth(ctx.Manager.SystemContext);
         pump.WithDeviceHealth(DeviceHealthEnumeration.NORMAL);
+
+        // The DeviceHealth child was added to the in-memory DeviceState
+        // subtree after the device itself was registered, so it must be
+        // registered with the manager explicitly. Without this the node
+        // is browsable but its attributes never resolve, so the DI
+        // companion-spec checker cannot map it to the declared DeviceHealth node.
+        await ctx.Manager
+            .AddPredefinedNodeAsync(pump.Device.DeviceHealth!, ctx.CancellationToken)
+            .ConfigureAwait(false);
+
         ((PumpNodeManager)ctx.Manager)
             .RegisterSupervisedDeviceHealth(pump.Device.DeviceHealth);
 

Libraries/Opc.Ua.Di.Server/Builders/SoftwareUpdateFacetWiring.cs

@@ -102,7 +102,13 @@ public static SoftwareUpdateState BuildAndAttach(
             su.BrowseName = new QualifiedName(SoftwareUpdateBrowseName, diNs);
             su.DisplayName = new LocalizedText(SoftwareUpdateBrowseName);
             su.NodeId = context.NodeIdFactory.New(context, su);
-            su.ReferenceTypeId = Types.ReferenceTypeIds.HasComponent;
+            // OPC 10000-100 models the SoftwareUpdate object as an AddIn on
+            // its host, referenced via HasAddIn (a subtype of HasComponent)
+            // rather than a plain HasComponent. Using HasAddIn keeps the
+            // facet spec-correct and lets companion-spec checkers treat it
+            // as an added-in component instead of validating it against the
+            // host type's OptionalPlaceholder children (GEN-07 noise).
+            su.ReferenceTypeId = Types.ReferenceTypeIds.HasAddIn;
             su.ModellingRuleId = NodeId.Null;
 
             // Loading subtype (the address-space slot is non-abstract;

Tests/Opc.Ua.Di.Tests/DeviceBuilderSoftwareUpdateTests.cs

@@ -85,6 +85,13 @@ public async Task WithSoftwareUpdateAttachesSoftwareUpdateSubtree()
                 "SoftwareUpdate child must be attached to the device.");
             Assert.That(su, Is.TypeOf<SoftwareUpdateState>(),
                 "SoftwareUpdate child must be a SoftwareUpdateState instance.");
+
+            // OPC 10000-100 models the SoftwareUpdate object as an AddIn,
+            // so it must be referenced from its host via HasAddIn rather
+            // than a plain HasComponent.
+            Assert.That(((BaseInstanceState)su!).ReferenceTypeId,
+                Is.EqualTo(Opc.Ua.Types.ReferenceTypeIds.HasAddIn),
+                "SoftwareUpdate must be attached via the HasAddIn reference.");
         }
 
         [Test]