feat(opcuaclient): #676 follow-ups — endpoint rewrite, stall wire test, fast definitive-loss recovery

- Endpoint rewrite: the driver now connects to the configured host AND port (scheme
  match, advertised path kept) instead of the server-advertised URL — fixes NAT/port-map
  upstreams and lets an in-test proxy carry the session (SDK SelectEndpoint rule).
- TcpStallProxy + OpcUaClientDriverStallWireTests: the in-place blip (#670) is now
  wire-tested on loopback — one Bad, frozen read stamp, same session, identical value
  republished Good, a post-recovery change arrives, no source-time regression after
  the SDK's late backlog flush.
- Defect found by that test, fixed: a change published right after a stall rode a
  Publish response the SDK timed out and never republished, leaving the node Good on
  the pre-change value indefinitely. New trailing reconcile read (Timeout +
  KeepAliveInterval after recovery) publishes any Good value newer than the last
  accepted one, through the replay guard's mark.
- IDriverConnectionLossSource (Core.Abstractions): opt-in definitive-loss signal.
  DriverInstanceActor attaches in PreStart / detaches in PostStop and turns a raise
  into a disconnect only while Connected. OpcUaClient raises once per session on
  keep-alive BadSessionIdInvalid/BadSessionClosed/BadSessionNotActivated/
  BadServerHalted (measured: the SDK never re-opens a halted channel) or a dropped
  subscription; ambiguous codes stay with the #527 watchdog.
- Replay guard: one Information summary per recovery when the window closes
  ("dropped N late notifications across M refs"), with a timer so quiet
  subscriptions log it too.
- ReconnectPeriod deleted (options, AdminUI form, docs, tests); stored configs that
  carry reconnectPeriod still parse in the factory, probe and browser.
- Docs: OpcUaClient.md, DriverLifecycle.md, driver-specs.md, CLAUDE.md.

tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests/OpcUaClientDriverPageFormSerializationTests.cs

@@ -34,7 +34,6 @@ public sealed class OpcUaClientDriverPageFormSerializationTests
             Timeout = TimeSpan.FromSeconds(20),
             SessionTimeout = TimeSpan.FromSeconds(180),
             KeepAliveInterval = TimeSpan.FromSeconds(10),
-            ReconnectPeriod = TimeSpan.FromSeconds(15),
             AutoAcceptCertificates = true,
             BrowseRoot = "i=85",
             MaxDiscoveredNodes = 5000,
@@ -58,7 +57,6 @@ public sealed class OpcUaClientDriverPageFormSerializationTests
         back.Timeout.ShouldBe(TimeSpan.FromSeconds(20));
         back.SessionTimeout.ShouldBe(TimeSpan.FromSeconds(180));
         back.KeepAliveInterval.ShouldBe(TimeSpan.FromSeconds(10));
-        back.ReconnectPeriod.ShouldBe(TimeSpan.FromSeconds(15));
         back.AutoAcceptCertificates.ShouldBeTrue();
         back.BrowseRoot.ShouldBe("i=85");
         back.MaxDiscoveredNodes.ShouldBe(5000);
@@ -105,7 +103,6 @@ public sealed class OpcUaClientDriverPageFormSerializationTests
             Timeout                  = TimeSpan.FromSeconds(12),
             SessionTimeout           = TimeSpan.FromSeconds(150),
             KeepAliveInterval        = TimeSpan.FromSeconds(7),
-            ReconnectPeriod          = TimeSpan.FromSeconds(8),
             AutoAcceptCertificates   = true,
             BrowseRoot               = "i=85",
             MaxDiscoveredNodes       = 3000,
@@ -133,7 +130,6 @@ public sealed class OpcUaClientDriverPageFormSerializationTests
         result.Timeout.ShouldBe(TimeSpan.FromSeconds(12));
         result.SessionTimeout.ShouldBe(TimeSpan.FromSeconds(150));
         result.KeepAliveInterval.ShouldBe(TimeSpan.FromSeconds(7));
-        result.ReconnectPeriod.ShouldBe(TimeSpan.FromSeconds(8));
         result.AutoAcceptCertificates.ShouldBeTrue();
         result.BrowseRoot.ShouldBe("i=85");
         result.MaxDiscoveredNodes.ShouldBe(3000);