fix(opcuaclient): upstream session loss goes Bad and recovers (#670)

A bad keep-alive now degrades health (LastSuccessfulRead preserved) and,
once per outage, publishes BadNoCommunication (value retained) for every
subscribed ref plus a quality-only annotation on subscribed alarm
conditions. Good keep-alives and data/event notifications advance
LastSuccessfulRead, so an idle-but-alive subscription never looks dead
to the #527 watchdog. A keep-alive that recovers on the same session
re-reads the Bad refs and republishes them Good; a session that does not
come back is recovered by the watchdog's ShutdownAsync + InitializeAsync
+ re-subscribe.

Deletes the SessionReconnectHandler wiring (it retried forever in SDK
1.5.378, cloned subscriptions the driver never re-tracked and kept health
Healthy), OnReconnectComplete, TryRearmReconnect and the reconnect_*
counters (new keepalive_recovered). Teardown of a lost session skips
wire deletes and bounds CloseSession. SDK warnings reach the driver log.
Wire test reworked: restart => Bad, then watchdog-style reinit => Good.

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.OpcUaClient.Contracts/OpcUaClientDriverOptions.cs

@@ -101,7 +101,10 @@ public sealed record OpcUaClientDriverOptions
     /// <summary>Client-side keep-alive interval.</summary>
     public TimeSpan KeepAliveInterval { get; init; } = TimeSpan.FromSeconds(5);
 
-    /// <summary>Initial reconnect delay after a session drop.</summary>
+    /// <summary>
+    ///     Retained for config compatibility only — no longer used (Gitea #670). The driver has no in-driver reconnect
+    ///     handler; a lost session is recovered by the host's comms-loss watchdog re-initialising the driver.
+    /// </summary>
     public TimeSpan ReconnectPeriod { get; init; } = TimeSpan.FromSeconds(5);
 
     /// <summary>