Add CriticalError_TransmitFailed to protobufs

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "cmake.configureOnOpen": false
+}

mesh.proto

@@ -777,6 +777,11 @@ enum CriticalErrorCode {
   // The channel tried to set a radio setting which is not supported by this chipset, 
   // radio comms settings are now undefined.
   InvalidRadioSetting = 7;
+
+  // Radio transmit hardware failure. We sent data to the radio chip, but it didn't
+  // reply with an interrupt.
+  TransmitFailed = 8;
+
 }
 
 /**