feat(dashboard): distinct 'forced' subtag provider badge

Render Fallback:Mode=ForceSubtag as a cyan 'Subtag monitoring (forced)'
badge, distinct from the amber failover 'degraded' badge, so an intentional
configuration isn't shown as a fault. Distinguished by the shared
AlarmProviderReasons.ForcedSubtag reason carried on the provider-status feed.

src/ZB.MOM.WW.MxGateway.Tests/Gateway/Dashboard/DashboardBrowseAndAlarmModelTests.cs

@@ -172,6 +172,28 @@ public sealed class DashboardBrowseAndAlarmModelTests
         Assert.Equal("x", model.Reason);
     }
 
+    /// <summary>
+    ///     Verifies that a configured forced-subtag provider status renders the
+    ///     distinct "forced" badge (cyan/info), not the amber failover-degraded one.
+    /// </summary>
+    [Fact]
+    public void FromProviderStatus_Subtag_ForcedReason_ForcedBadge()
+    {
+        AlarmProviderStatus status = new()
+        {
+            Mode = AlarmProviderMode.Subtag,
+            Degraded = true,
+            Reason = ZB.MOM.WW.MxGateway.Server.Alarms.AlarmProviderReasons.ForcedSubtag,
+        };
+
+        DashboardAlarmProviderStatus model = DashboardAlarmProviderStatus.FromProviderStatus(status);
+
+        Assert.True(model.IsDegraded);
+        Assert.Equal(DashboardAlarmProviderStatus.ForcedSubtagLabel, model.Label);
+        Assert.Contains("bg-info", model.BadgeCssClass, StringComparison.Ordinal);
+        Assert.DoesNotContain("bg-warning", model.BadgeCssClass, StringComparison.Ordinal);
+    }
+
     /// <summary>Verifies that the formatter renders array elements and element type correctly.</summary>
     [Fact]
     public void FormatValue_AndDataType_RenderArrayElementsAndElementType()