[FL-1885] USB-UART bridge (#778)

* [FL-1885] USB-UART: app and worker
* [FL-1885] USB-UART: UART on CDC0

Co-authored-by: Aleksandr Kutuzov <alleteam@gmail.com>

applications/debug_tools/bad_usb.c

@@ -248,6 +248,8 @@ static void badusb_worker(void* context) {
     evt.worker.state = WorkerStateDone;
     osMessageQueuePut(app->event_queue, &evt, 0, osWaitForever);
 
+    furi_hal_hid_kb_release_all();
+
     osThreadExit();
 }