Auto: abcip-3.1 — configurable CIP connection size per device

Closes #235

src/ZB.MOM.WW.OtOpcUa.Driver.AbCip/AbCipDriverOptions.cs

@@ -87,6 +87,14 @@ public sealed class AbCipDriverOptions
     ///     1 second — matches typical SCADA alarm-refresh conventions.
     /// </summary>
     public TimeSpan AlarmPollInterval { get; init; } = TimeSpan.FromSeconds(1);
+
+    /// <summary>
+    ///     PR abcip-3.1 — optional sink for non-fatal driver warnings (legacy-firmware
+    ///     <c>ConnectionSize</c> mis-match, etc.). Production hosting wires this to Serilog;
+    ///     unit tests pin a list-collecting lambda to assert which warnings fired. <c>null</c>
+    ///     swallows warnings — convenient for back-compat deployments that don't care.
+    /// </summary>
+    public Action<string>? OnWarning { get; init; }
 }
 
 /// <summary>
@@ -98,10 +106,19 @@ public sealed class AbCipDriverOptions
 /// <param name="PlcFamily">Which per-family profile to apply. Determines ConnectionSize,
 ///     request-packing support, unconnected-only hint, and other quirks.</param>
 /// <param name="DeviceName">Optional display label for Admin UI. Falls back to <see cref="HostAddress"/>.</param>
+/// <param name="ConnectionSize">PR abcip-3.1 — optional override for the family-default
+///     <see cref="PlcFamilies.AbCipPlcFamilyProfile.DefaultConnectionSize"/>. Threads through to
+///     libplctag's <c>connection_size</c> attribute on the underlying tag handle so operators can
+///     dial the CIP Forward Open buffer down for legacy firmware (v19-and-earlier ControlLogix
+///     caps at 504) or up for high-throughput shops on FW20+. Validated against the Kepware
+///     supported range [500..4002] at <c>InitializeAsync</c>; out-of-range values fault the
+///     driver. <c>null</c> uses the family default — back-compat with deployments that haven't
+///     touched the knob.</param>
 public sealed record AbCipDeviceOptions(
     string HostAddress,
     AbCipPlcFamily PlcFamily = AbCipPlcFamily.ControlLogix,
-    string? DeviceName = null);
+    string? DeviceName = null,
+    int? ConnectionSize = null);
 
 /// <summary>
 ///     One AB-backed OPC UA variable. Mirrors the <c>ModbusTagDefinition</c> shape.