fix: Remove hot-path logging and wall-clock calls from PinMAME callbacks.

The solenoid-delay timing check now uses a monotonic `Stopwatch`-based timestamp instead of `DateTimeOffset.Now`, and high-frequency coil callback logs were downgraded behind `Logger.IsDebugEnabled` so normal runtime no longer pays string-format/logging cost on every coil edge.

Author: freezy

VisualPinball.Engine.PinMAME.Unity/Runtime/PinMameGamelogicEngine.cs

@@ -225,6 +225,7 @@ public void ApplySharedState(in SimulationState.Snapshot snapshot)
 		private bool _dispatchQueueWarningIssued;
 		private bool _simulationCoilQueueWarningIssued;
 		private bool _simulationCoilQueueDropWarningIssued;
+		private long _solenoidDelayStartTimestampUsec;
 		private const int MaxSimulationCoilDispatchQueueSize = 8192;
 		private const int DispatchQueueWarningThreshold = 512;
 		private const double PerfSampleWindowSeconds = 0.25;
@@ -239,7 +240,7 @@ public void ApplySharedState(in SimulationState.Snapshot snapshot)
 		private bool _sharedLampPlaybackActive;
 		private readonly Queue<float[]> _audioQueue = new();
 
-		private int _audioFilterChannels;
+		private int _audioFilterChannels;
 		private PinMameAudioInfo _audioInfo;
 		private float[] _lastAudioFrame = {};
 		private int _lastAudioFrameOffset;
@@ -259,6 +260,8 @@ public void ApplySharedState(in SimulationState.Snapshot snapshot)
 		private bool _toggleSpeed = false;
 		private Keyboard _keyboard;
 
+		private static long TimestampUsec => (Stopwatch.GetTimestamp() * 1_000_000) / Stopwatch.Frequency;
+
 		private static readonly SemaphoreSlim PinMameStartStopGate = new SemaphoreSlim(1, 1);
 		private int _onInitCalled;
 		private int _stopRequested;
@@ -733,7 +736,8 @@ private void OnGameStarted()
 			Logger.Info("[PinMAME] Game started.");
 			_isRunning = true;
 
-			_solenoidDelayStart = DateTimeOffset.Now.ToUnixTimeMilliseconds();
+			_solenoidDelayStartTimestampUsec = TimestampUsec;
+			_solenoidDelayStart = _solenoidDelayStartTimestampUsec / 1000;
 
 			try {
 				SendInitialSwitches();
@@ -1141,13 +1145,13 @@ private void OnSolenoidUpdated(int id, bool isActive)
 			MarkPinMameCallbackActivity();
 
 			if (_pinMameIdToCoilIdMapping.ContainsKey(id)) {
-				if (!_solenoidsEnabled) {
-					_solenoidsEnabled = DateTimeOffset.Now.ToUnixTimeMilliseconds() - _solenoidDelayStart >= SolenoidDelay;
-
-					if (_solenoidsEnabled) {
-						Logger.Info($"Solenoids enabled, {SolenoidDelay}ms passed");
-					}
-				}
+				if (!_solenoidsEnabled) {
+					_solenoidsEnabled = TimestampUsec - _solenoidDelayStartTimestampUsec >= (long)(SolenoidDelay * 1000f);
+
+					if (_solenoidsEnabled) {
+						Logger.Info($"Solenoids enabled, {SolenoidDelay}ms passed");
+					}
+				}
 
 				var coil = _coils[_pinMameIdToCoilIdMapping[id]];
 
@@ -1156,7 +1160,9 @@ private void OnSolenoidUpdated(int id, bool isActive)
 						_sharedCoilStates[id] = isActive;
 					}
 
-					Logger.Info($"[PinMAME] <= coil {coil.Id} : {isActive} | {coil.Description}");
+					if (Logger.IsDebugEnabled) {
+						Logger.Debug($"[PinMAME] <= coil {coil.Id} : {isActive} | {coil.Description}");
+					}
 					if (ShouldDispatchSimulationCoil(coil.Id)) {
 						_simulationCoilDispatchQueue.Enqueue(new CoilEventArgs(coil.Id, isActive));
 						var simulationCoilQueueSize = Interlocked.Increment(ref _simulationCoilDispatchQueueSize);
@@ -1179,9 +1185,11 @@ private void OnSolenoidUpdated(int id, bool isActive)
 
 					EnqueueMainThreadDispatch(() => OnCoilChanged?.Invoke(this, new CoilEventArgs(coil.Id, isActive)));
 				}
-				else {
-					Logger.Info($"[PinMAME] <= solenoids disabled, coil {coil.Id} : {isActive} | {coil.Description}");
-				}
+				else {
+					if (Logger.IsDebugEnabled) {
+						Logger.Debug($"[PinMAME] <= solenoids disabled, coil {coil.Id} : {isActive} | {coil.Description}");
+					}
+				}
 			}
 			else {
 				Logger.Warn($"[PinMAME] <= coil UNMAPPED {id}: {isActive}");