docs(opcuaclient): #657 review — correct stale rebuild comment, note cold-host residual

Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe

docs/AlarmTracking.md

@@ -98,7 +98,7 @@ same condition is wired as an **event notifier of every referencing equipment fo
   flagged — so a host already showing that state writes nothing, and a host that retained the condition Active gets a
   real "Cleared". Pre-#657 a respawn wrote a duplicate "Activated" + "Cleared" pair per inactive+unacked condition, and
   an inactive+acked first sight went out as `Unspecified` (an "Activated" row for an inactive alarm; a retained-Active
-  condition was never cleared). E2E: `Runtime.Tests/NativeAlarmRestatementEndToEndTests`.
+  condition was never cleared). Residual (pre-existing, not a regression): a cold host treats an unseen condition as acked, so after a node restart each upstream inactive+unacked condition still writes "Activated" + "Cleared" once. E2E: `Runtime.Tests/NativeAlarmRestatementEndToEndTests`.
 
 ### Native condition state survives a full rebuild (Gitea #641)
 

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient/OpcUaClientDriver.cs

@@ -1887,9 +1887,10 @@ public sealed class OpcUaClientDriver : IDriver, ITagDiscovery, IReadable, IWrit
 
     /// <summary>
     ///     #619 re-review: open (or re-open) the host's alarm subscription over <paramref name="sourceNodeIds"/>.
-    ///     A CHANGED set means the host rebuilt its address space (an alarm-bearing delta always does), recreating
-    ///     every condition node inactive+acked — so every last-told state is forgotten and the post-subscribe
-    ///     ConditionRefresh re-reports from that default. The SAME set (a reinit / reconnect re-subscribe) keeps
+    ///     A CHANGED set means the host applied an alarm-bearing delta, so every last-told state is forgotten and the
+    ///     post-subscribe ConditionRefresh re-reports as first sight. Since #641 a rebuild KEEPS native condition state,
+    ///     so the host may hold ANY state here — which is why first sight is flagged (#656/#657) rather than assuming
+    ///     an inactive+acked default. The SAME set (a reinit / reconnect re-subscribe) keeps
     ///     them, so the refresh copy of an already-reported state emits nothing. Ack targets of refs no longer
     ///     subscribed are pruned either way.
     /// </summary>