fix(driver-ablegacy): resolve Medium code-review finding (Driver.AbLegacy-009)

InitializeAsync catch block now mirrors ShutdownAsync teardown: cancels
and disposes probe CancellationTokenSources, calls DisposeRuntimes, and
clears _devices/_tagsByName before rethrowing. A caller that catches and
abandons (rather than retrying via ReinitializeAsync) no longer leaves
orphaned probe tasks or libplctag handles alive.

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

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy/AbLegacyDriver.cs

@@ -74,6 +74,20 @@ public sealed class AbLegacyDriver : IDriver, IReadable, IWritable, ITagDiscover
         catch (Exception ex)
         {
             _health = new DriverHealth(DriverState.Faulted, null, ex.Message);
+            // Tear down any probe loops and cached state that were created before the failure so
+            // that a caller who catches and abandons (rather than retrying via ReinitializeAsync)
+            // doesn't leave orphaned background tasks, CancellationTokenSources, and libplctag
+            // handles alive. Mirrors the body of ShutdownAsync without awaiting the poll engine
+            // (nothing has been subscribed yet at init time).
+            foreach (var state in _devices.Values)
+            {
+                try { state.ProbeCts?.Cancel(); } catch { }
+                state.ProbeCts?.Dispose();
+                state.ProbeCts = null;
+                state.DisposeRuntimes();
+            }
+            _devices.Clear();
+            _tagsByName.Clear();
             throw;
         }
         return Task.CompletedTask;