feat(alarms): condition Quality tracks source connectivity (#477)

Part 9 ConditionType.Quality was never assigned; default(StatusCode)==Good
so every native + scripted condition reported Good unconditionally — a
comms-lost device still showed a healthy, inactive, Good condition (a
wrong-VALUE bug, distinct from the null-value #473/#475). Clients (and HMIs
bucketing on IsGood) could not tell "genuinely inactive" from "lost contact".

Layer 1 — make Quality a real, plumbed field:
- AlarmConditionSnapshot gains OpcUaQuality Quality (default Good).
- MaterialiseAlarmCondition sets it (native BadWaitingForInitialData, scripted Good).
- WriteAlarmCondition projects snapshot.Quality; the delta-gate gains a Quality
  member so a quality-bucket change fires a Part 9 event.

Layer 2 — drive native quality from driver connectivity (a comms-lost driver
emits no alarm transitions, and an alarm-bearing raw tag has no value variable,
so quality can't come from either existing channel):
- DriverInstanceActor Tells parent ConnectivityChanged on Connected/Reconnecting.
- DriverHostActor fans it to every native condition the driver owns as
  OpcUaPublishActor.AlarmQualityUpdate (Good on connect, Bad on disconnect).
- New dedicated IOpcUaAddressSpaceSink.WriteAlarmQuality sets ONLY Quality and
  fires only on a bucket change — never touches Active/Acked/Retain (an active
  alarm that loses comms stays active). Not a full-snapshot re-projection, so it
  can't clobber severity/message and works for a never-fired condition.
  Forwarded through DeferredAddressSpaceSink (F10b trap; auto-verified by the
  reflection forwarding guard). Ungated by redundancy role; no /alerts row.

Scripted conditions stay Good; worst-of-input quality deferred to #478 (Layer 3).

Tests: node-level (materialise/project/no-clobber/unknown-node no-op),
NativeAlarmProjector, DriverInstanceActor connectivity emission, DriverHostActor
fan-out, OpcUaPublishActor routing, and the wire-level guard
(Condition_event_Quality_tracks_source_connectivity_on_the_wire) — RED-verified
against a simulated pre-fix always-Good server. Existing DriverInstanceActor
parent probes ignore the new ConnectivityChanged.

Docs: docs/AlarmTracking.md §"Condition source-data Quality (#477)";
design doc docs/plans/2026-07-17-alarm-condition-quality-477-design.md.

tests/Server/ZB.MOM.WW.OtOpcUa.OpcUaServer.Tests/SdkAddressSpaceSinkTests.cs

@@ -523,7 +523,8 @@ public sealed class SdkAddressSpaceSinkTests : IDisposable
     {
         var baseState = new OtOpcUaNodeManager.AlarmConditionDelta(
             Active: true, Acknowledged: false, Confirmed: true, Enabled: true,
-            Shelving: AlarmShelvingKind.Unshelved, MappedSeverity: 100, Message: "m");
+            Shelving: AlarmShelvingKind.Unshelved, MappedSeverity: 100, Message: "m",
+            Quality: StatusCodes.Good);
 
         // Equal ⇒ suppress (this is the inbound double-emit case in pure form).
         OtOpcUaNodeManager.ShouldFireConditionEvent(baseState, baseState).ShouldBeFalse();
@@ -537,6 +538,8 @@ public sealed class SdkAddressSpaceSinkTests : IDisposable
         OtOpcUaNodeManager.ShouldFireConditionEvent(baseState, baseState with { Shelving = AlarmShelvingKind.Timed }).ShouldBeTrue();
         OtOpcUaNodeManager.ShouldFireConditionEvent(baseState, baseState with { MappedSeverity = 900 }).ShouldBeTrue();
         OtOpcUaNodeManager.ShouldFireConditionEvent(baseState, baseState with { Message = "other" }).ShouldBeTrue();
+        // #477 — a quality-only change (e.g. source going comms-lost, no state change) is a genuine delta.
+        OtOpcUaNodeManager.ShouldFireConditionEvent(baseState, baseState with { Quality = StatusCodes.Bad }).ShouldBeTrue();
     }
 
     /// <summary>T20 — null-vs-empty Message normalization. Both snapshot.Message = null and a live node
@@ -552,7 +555,8 @@ public sealed class SdkAddressSpaceSinkTests : IDisposable
         // Both null and "" collapse to string.Empty in AlarmConditionDelta — they are the same delta value.
         var withNull = new OtOpcUaNodeManager.AlarmConditionDelta(
             Active: false, Acknowledged: true, Confirmed: true, Enabled: true,
-            Shelving: AlarmShelvingKind.Unshelved, MappedSeverity: 100, Message: string.Empty);
+            Shelving: AlarmShelvingKind.Unshelved, MappedSeverity: 100, Message: string.Empty,
+            Quality: StatusCodes.Good);
 
         var withEmpty = withNull with { Message = string.Empty };