fix(driver-s7-cli): resolve Low code-review findings (Driver.S7.Cli-004,005,006,007)

- Driver.S7.Cli-004: 'await using var driver' is the sole driver
  disposal path; dropped the redundant explicit await ShutdownAsync from
  each command's finally.
- Driver.S7.Cli-005: deleted the stale empty
  tests/ZB.MOM.WW.OtOpcUa.Driver.S7.Cli.Tests/ directory (the real test
  project lives under tests/Drivers/Cli/).
- Driver.S7.Cli-006: S7CommandBaseBuildOptionsTests cover the probe
  toggle, timeout mapping, host/port/CPU/rack/slot wiring, and tag list
  passthrough.
- Driver.S7.Cli-007: re-added the SubscribeCommand handler comment
  explaining the CliFx IConsole.Output usage and that the poll-thread
  raises events.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

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

@@ -33,6 +33,9 @@ public sealed class ProbeCommand : S7CommandBase
             Writable: false);
         var options = BuildOptions([probeTag]);
 
+        // Driver.S7.Cli-004: `await using` is the sole disposal mechanism — S7Driver.DisposeAsync
+        // already invokes ShutdownAsync, so the previous explicit ShutdownAsync(CancellationToken.None)
+        // call in a finally block ran shutdown twice. The await-using on the next line is enough.
         await using var driver = new S7Driver(options, DriverInstanceId);
         // Driver.S7.Cli-003: wrap the entire probe sequence so that a refused/unreachable TCP
         // connect still prints the structured Host/CPU/Health lines instead of crashing with a
@@ -66,9 +69,5 @@ public sealed class ProbeCommand : S7CommandBase
             if (health.LastError is { } err)
                 await console.Output.WriteLineAsync($"Last error:   {err}");
         }
-        finally
-        {
-            await driver.ShutdownAsync(CancellationToken.None);
-        }
     }
 }

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

@@ -45,17 +45,13 @@ public sealed class ReadCommand : S7CommandBase
             StringLength: StringLength);
         var options = BuildOptions([tag]);
 
+        // Driver.S7.Cli-004: `await using` is the sole disposal mechanism — S7Driver.DisposeAsync
+        // 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);
-        try
-        {
-            await driver.InitializeAsync("{}", ct);
-            var snapshot = await driver.ReadAsync([tagName], ct);
-            await console.Output.WriteLineAsync(SnapshotFormatter.Format(Address, snapshot[0]));
-        }
-        finally
-        {
-            await driver.ShutdownAsync(CancellationToken.None);
-        }
+        await driver.InitializeAsync("{}", ct);
+        var snapshot = await driver.ReadAsync([tagName], ct);
+        await console.Output.WriteLineAsync(SnapshotFormatter.Format(Address, snapshot[0]));
     }
 
     /// <summary>Tag-name key used internally. Address + type is already unique.</summary>

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

@@ -37,12 +37,20 @@ public sealed class SubscribeCommand : S7CommandBase
             Writable: false);
         var options = BuildOptions([tag]);
 
+        // Driver.S7.Cli-004: `await using` is the sole driver-disposal mechanism — S7Driver.DisposeAsync
+        // already invokes ShutdownAsync, so a redundant ShutdownAsync(CancellationToken.None) in finally
+        // ran shutdown twice. Only UnsubscribeAsync stays in the finally block — that's a subscription
+        // lifecycle concern that is not part of driver disposal.
         await using var driver = new S7Driver(options, DriverInstanceId);
         ISubscriptionHandle? handle = null;
         try
         {
             await driver.InitializeAsync("{}", ct);
 
+            // Driver.S7.Cli-007: route every data-change event to the CliFx console (not
+            // System.Console — the analyzer flags it + IConsole is the testable abstraction).
+            // The handler is synchronous because OnDataChange is raised from a driver
+            // background thread; the IConsole.Output writer is thread-safe for line writes.
             driver.OnDataChange += (_, e) =>
             {
                 var line = $"[{DateTime.UtcNow:HH:mm:ss.fff}] " +
@@ -71,7 +79,6 @@ public sealed class SubscribeCommand : S7CommandBase
                 try { await driver.UnsubscribeAsync(handle, CancellationToken.None); }
                 catch { /* teardown best-effort */ }
             }
-            await driver.ShutdownAsync(CancellationToken.None);
         }
     }
 }

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

@@ -52,17 +52,13 @@ public sealed class WriteCommand : S7CommandBase
 
         var parsed = ParseValue(Value, DataType);
 
+        // Driver.S7.Cli-004: `await using` is the sole disposal mechanism — S7Driver.DisposeAsync
+        // 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);
-        try
-        {
-            await driver.InitializeAsync("{}", ct);
-            var results = await driver.WriteAsync([new WriteRequest(tagName, parsed)], ct);
-            await console.Output.WriteLineAsync(SnapshotFormatter.FormatWrite(Address, results[0]));
-        }
-        finally
-        {
-            await driver.ShutdownAsync(CancellationToken.None);
-        }
+        await driver.InitializeAsync("{}", ct);
+        var results = await driver.WriteAsync([new WriteRequest(tagName, parsed)], ct);
+        await console.Output.WriteLineAsync(SnapshotFormatter.FormatWrite(Address, results[0]));
     }
 
     /// <summary>Parse <c>--value</c> per <see cref="S7DataType"/>, invariant culture throughout.</summary>