review(Driver.S7.Cli): endpoint validation + cancellation/flush/write-lock consistency

Re-review at 7286d320. -008 (Medium): S7CommandBase.ValidateEndpoint (port range + timeout>0)
in all commands +tests. -009 clean OperationCanceledException handling; -010 FlushLogging()
in subscribe finally; -011 lock console writes in OnDataChange. -012 (Verdict headline) deferred.

src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.S7.Cli/Commands/WriteCommand.cs

@@ -43,6 +43,7 @@ public sealed class WriteCommand : S7CommandBase
     public override async ValueTask ExecuteAsync(IConsole console)
     {
         ConfigureLogging();
+        ValidateEndpoint();
         var ct = console.RegisterCancellationHandler();
 
         var tagName = ReadCommand.SynthesiseTagName(Address, DataType);
@@ -60,9 +61,18 @@ public sealed class WriteCommand : S7CommandBase
         // already invokes ShutdownAsync, so a redundant explicit ShutdownAsync(CancellationToken.None)
         // in a finally block ran shutdown twice. The await-using on the next line is enough.
         await using var driver = new S7Driver(options, DriverInstanceId);
-        await driver.InitializeAsync("{}", ct);
-        var results = await driver.WriteAsync([new WriteRequest(tagName, parsed)], ct);
-        await console.Output.WriteLineAsync(SnapshotFormatter.FormatWrite(Address, results[0]));
+        try
+        {
+            await driver.InitializeAsync("{}", ct);
+            var results = await driver.WriteAsync([new WriteRequest(tagName, parsed)], ct);
+            await console.Output.WriteLineAsync(SnapshotFormatter.FormatWrite(Address, results[0]));
+        }
+        catch (OperationCanceledException) when (ct.IsCancellationRequested)
+        {
+            // Driver.S7.Cli-009: Ctrl+C during driver connect/write — exit quietly so
+            // CliFx does not render a full stack trace for a user-initiated cancellation.
+            await console.Output.WriteLineAsync("Cancelled.");
+        }
     }
 
     /// <summary>Parse <c>--value</c> per <see cref="S7DataType"/>, invariant culture throughout.</summary>