stops creating the HVRCommsUtil on quitting

Author: dooly123

Basis/Packages/dev.hai-vr.basis.comms/Scripts/Systems/Runtime/Networking/HVRCommsUtil.cs

@@ -9,9 +9,25 @@ namespace HVR.Basis.Comms
 {
     public static class HVRCommsUtil
     {
+        private static bool _applicationIsQuitting;
+
+        [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
+        private static void InitializeQuitGuard()
+        {
+            _applicationIsQuitting = false;
+            Application.quitting -= OnApplicationQuitting;
+            Application.quitting += OnApplicationQuitting;
+        }
+
+        private static void OnApplicationQuitting()
+        {
+            _applicationIsQuitting = true;
+        }
+
         public static T GetOrCreateSceneInstance<T>(ref T instance) where T : Component
         {
             if (instance != null) return instance;
+            if (_applicationIsQuitting) return null;
 
             var go = new GameObject($"HVR.{typeof(T).Name}");
             Object.DontDestroyOnLoad(go);

Basis/Packages/dev.hai-vr.basis.comms/Scripts/Systems/Runtime/OSC/BasisOscService.cs

@@ -197,7 +197,7 @@ public static void PublishValue(string address, OscData value)
 
         public static void PublishValues(string address, OscData[] values)
         {
-            OSCAcquisitionServer.SceneInstance.PublishValues(address, values);
+            OSCAcquisitionServer.SceneInstance?.PublishValues(address, values);
         }
 
         public static void UpdateSubscriptions(EntityId ownerId, bool receiveAll, IEnumerable<string> subscribedAddresses, IEnumerable<string> subscribedPrefixes)
@@ -219,7 +219,7 @@ public static void UpdateSubscriptions(EntityId ownerId, bool receiveAll, IEnume
                 RebuildDispatcherState_NoLock();
             }
             // (eventual consistency is acceptable) and this avoids a potential deadlock if the acquisition server needs to call back into this service while processing the subscription update.
-            OSCAcquisitionServer.SceneInstance.UpdateSubscriptions(ownerId, exactAddresses, prefixAddresses);
+            OSCAcquisitionServer.SceneInstance?.UpdateSubscriptions(ownerId, exactAddresses, prefixAddresses);
         }
 
         public static void UpdateSubscriptions(EntityId ownerId, IEnumerable<string> subscribedAddresses, IEnumerable<string> subscribedPrefixes)
@@ -240,7 +240,7 @@ public static void ClearSubscriptions(EntityId ownerId)
                 }
             }
 
-            OSCAcquisitionServer.SceneInstance.ClearSubscriptions(ownerId);
+            OSCAcquisitionServer.SceneInstance?.ClearSubscriptions(ownerId);
         }
 
         private static void RebuildDispatcherState_NoLock()