[core] Move non-interface classes to libraries

arduino/libretuya/libraries/NetUtils/api/IPv6Address.h

@@ -0,0 +1,3 @@
+#pragma once
+
+#include "../IPv6Address.h"

arduino/realtek-ambz/libraries/WiFi/WiFiClient.h

@@ -1,7 +1,7 @@
 #pragma once
 
-#include <api/LwIPRxBuffer.h>
 #include <api/WiFiClient.h>
+#include <LwIPRxBuffer.h>
 #include <memory>
 
 class SocketHandle;

builder/arduino-common.py

@@ -21,6 +21,7 @@ env.Prepend(
         join(LT_API_DIR, "compat"),
         join(LT_API_DIR, "libraries", "base64"),
         join(LT_API_DIR, "libraries", "HTTPClient"),
+        join(LT_API_DIR, "libraries", "NetUtils"),
         join(LT_API_DIR, "libraries", "WebServer"),
         join(LT_API_DIR, "libraries", "WiFiMulti"),
         # fmt: on