Auto: abcip-5.2 — HSBY failover routing in ResolveHost

Closes #243

tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/AbCipHsbyFailoverTests.cs

@@ -0,0 +1,47 @@
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.Driver.AbCip;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests;
+
+/// <summary>
+///     PR abcip-5.2 — integration scaffold for HSBY failover routing through
+///     <see cref="AbCipDriver.ResolveHost"/>. Skipped by default because the paired
+///     fixture (controllogix-secondary <c>ab_server</c> instance + <c>hsby-mux</c>
+///     sidecar that flips the role tag on demand) is not yet stable in the Docker
+///     compose layout. The scaffold lives here so:
+///     <list type="bullet">
+///         <item>The trait is discoverable by <c>dotnet test --filter "Category=Hsby"</c>.</item>
+///         <item>The companion E2E script (<c>scripts/e2e/test-abcip-hsby.ps1</c>) has a
+///             paired surface already wired in tests when an operator stands up the fixture
+///             manually.</item>
+///         <item>A future PR can flip the skip into a real assertion without restructuring
+///             the test layout.</item>
+///     </list>
+///     The unit-level coverage in <c>AbCipHsbyFailoverTests</c> (in the unit tests
+///     project) exercises the active-address-routing + cache-invalidation contract in
+///     full against the FakeAbCipTagFactory; this scaffold is just the wire-level shape.
+/// </summary>
+[Trait("Category", "Hsby")]
+[Trait("Requires", "AbServer")]
+public sealed class AbCipHsbyFailoverTests
+{
+    [AbServerFact]
+    public Task ResolveHost_routes_to_partner_after_role_flip_through_hsby_mux()
+    {
+        // The paired-fixture compose service (controllogix + controllogix-secondary +
+        // hsby-mux sidecar at http://localhost:7080) is not yet wired. When it ships,
+        // the test body will:
+        //   1. POST {"active": "primary"} to hsby-mux → assert ResolveHost = primary
+        //      gateway via a CLI read.
+        //   2. POST {"active": "partner"} → wait for the probe loop to catch up →
+        //      assert ResolveHost = partner gateway via a second CLI read.
+        //   3. Assert AbCip.HsbyFailoverCount on the driver's diagnostics
+        //      ≥ 1 by reading the driver-diagnostics RPC through the OPC UA Admin
+        //      surface.
+        Assert.Skip("HSBY paired fixture (controllogix-secondary + hsby-mux sidecar) " +
+            "not yet promoted out of scaffold. Run scripts/e2e/test-abcip-hsby.ps1 against a " +
+            "manually-stood-up paired fixture when verifying this PR end-to-end.");
+        return Task.CompletedTask;
+    }
+}