fix: send device interface list on client join

In order to avoid updating the MC Edge API to send device interfaces, one of the responses to the clientJoined message will now be a message with the type `/system/deviceInterfaces`. This has a corresponding handler in the core library to put the interfaces in the correct location.

src/PepperDash.Essentials.MobileControl/MobileControlSystemController.cs

@@ -2185,6 +2185,8 @@ namespace PepperDash.Essentials
                 };
 
                 SendMessageObject(message);
+
+                SendDeviceInterfaces(clientId);
                 return;
             }
 
@@ -2196,7 +2198,10 @@ namespace PepperDash.Essentials
                     ClientId = clientId,
                     Content = roomKey
                 };
+
                 SendMessageObject(message);
+
+                SendDeviceInterfaces(clientId);
                 return;
             }
 
@@ -2214,6 +2219,8 @@ namespace PepperDash.Essentials
                 };
 
                 SendMessageObject(message);
+
+                SendDeviceInterfaces(clientId);
                 return;
             }
 
@@ -2227,6 +2234,36 @@ namespace PepperDash.Essentials
             };
 
             SendMessageObject(newMessage);
+
+            SendDeviceInterfaces(clientId);
+        }
+
+        private void SendDeviceInterfaces(string clientId)
+        {
+            this.LogDebug("Sending Device interfaces");
+            var devices = DeviceManager.GetDevices();
+            Dictionary<string, DeviceInterfaceInfo> deviceInterfaces = new Dictionary<string, DeviceInterfaceInfo>();
+
+            foreach (var device in devices)
+            {
+                var interfaces = device?.GetType().GetInterfaces().Select((i) => i.Name).ToList() ?? new List<string>();
+
+                deviceInterfaces.Add(device.Key, new DeviceInterfaceInfo
+                {
+                    Key = device.Key,
+                    Name = (device as IKeyName)?.Name ?? "",
+                    Interfaces = interfaces
+                });
+            }
+
+            var message = new MobileControlMessage
+            {
+                Type = "/system/deviceInterfaces",
+                ClientId = clientId,
+                Content = JToken.FromObject(new { deviceInterfaces })
+            };
+
+            SendMessageObject(message);
         }
 
         private void HandleUserCode(JToken content, Action<string, string> action = null)