refactor(health.akka): review polish (internal decision helper, role guard, factory results, test coverage) + fix SPEC §4 gate description

ZB.MOM.WW.Health/tests/ZB.MOM.WW.Health.Akka.Tests/ActiveNodeDecisionTests.cs

@@ -31,7 +31,7 @@ public sealed class ActiveNodeDecisionTests
 
     // Role-filtered: requiredRole != null.
     //   lacks role               -> Healthy (probe irrelevant for this node)
-    //   has role & is leader     -> Healthy
+    //   has role & is leader     -> Healthy (selfUp is ignored — role-filtered mode only cares about leadership)
     //   has role & not leader    -> Degraded
     public static IEnumerable<object[]> RoleFilteredCases() => new[]
     {
@@ -39,8 +39,10 @@ public sealed class ActiveNodeDecisionTests
         new object[] { true, true, false, "admin", HealthStatus.Healthy },
         new object[] { true, false, false, "admin", HealthStatus.Healthy },
         new object[] { false, false, false, "admin", HealthStatus.Healthy },
-        // node carries the role and is leader -> Healthy
+        // node carries the role and is leader -> Healthy (selfUp=true)
         new object[] { true, true, true, "admin", HealthStatus.Healthy },
+        // node carries the role and is leader -> Healthy (selfUp=false: role-filtered mode ignores selfUp)
+        new object[] { false, true, true, "admin", HealthStatus.Healthy },
         // node carries the role but is not leader -> Degraded
         new object[] { true, false, true, "admin", HealthStatus.Degraded },
         new object[] { false, false, true, "admin", HealthStatus.Degraded },

ZB.MOM.WW.Health/tests/ZB.MOM.WW.Health.Akka.Tests/AkkaClusterStatusPolicyTests.cs

@@ -23,6 +23,7 @@ public sealed class AkkaClusterStatusPolicyTests
         new object[] { MemberStatus.WeaklyUp, HealthStatus.Unhealthy },
         new object[] { MemberStatus.Down, HealthStatus.Unhealthy },
         new object[] { MemberStatus.Removed, HealthStatus.Unhealthy },
+        new object[] { (MemberStatus)99, HealthStatus.Unhealthy },   // unknown / future status
     };
 
     [Theory]
@@ -41,6 +42,7 @@ public sealed class AkkaClusterStatusPolicyTests
         new object[] { MemberStatus.WeaklyUp, HealthStatus.Degraded },
         new object[] { MemberStatus.Down, HealthStatus.Degraded },
         new object[] { MemberStatus.Removed, HealthStatus.Degraded },
+        new object[] { (MemberStatus)99, HealthStatus.Degraded },    // unknown / future status
     };
 
     [Theory]

ZB.MOM.WW.Health/tests/ZB.MOM.WW.Health.Akka.Tests/ZB.MOM.WW.Health.Akka.Tests.csproj

@@ -9,7 +9,6 @@
     <PackageReference Include="Microsoft.NET.Test.Sdk" />
     <PackageReference Include="xunit" />
     <PackageReference Include="xunit.runner.visualstudio" />
-    <PackageReference Include="Akka.TestKit.Xunit2" />
   </ItemGroup>
 
   <ItemGroup>