BLE based logging (#4146)

* WIP log characteristic

* Bluetooth logging plumbing

* Characteristic

* Callback

* Check for nullptr

* Esp32 bluetooth impl

* Formatting

* Add thread name and log level

* Add settings guard

* Remove comments

* Field name

* Fixes esp32

* Open it up

* Whoops

* Move va_end past our logic

src/nimble/NimbleBluetooth.h

@@ -11,6 +11,7 @@ class NimbleBluetooth : BluetoothApi
     bool isActive();
     bool isConnected();
     int getRssi();
+    void sendLog(const char *logMessage);
 
   private:
     void setupService();