Merge TactilityHeadless into Tactility (#263)

There currently is no practical use to have TactilityHeadless as a subproject. I'm merging it with the Tactility project.

Tactility/Source/hal/usb/UsbMock.cpp

@@ -0,0 +1,21 @@
+#ifndef ESP_PLATFORM
+
+#include "Tactility/hal/usb/Usb.h"
+
+#define TAG "usb"
+
+namespace tt::hal::usb {
+
+bool startMassStorageWithSdmmc() { return false; }
+void stop() {}
+Mode getMode() { return Mode::Default; }
+bool isSupported() { return false; }
+
+bool canRebootIntoMassStorageSdmmc() { return false; }
+void rebootIntoMassStorageSdmmc() {}
+bool isUsbBootMode() { return false; }
+void resetUsbBootMode() {}
+
+}
+
+#endif