LibDevTools+LibWebView+WebContent: Selectively fetch DOM node properties

When we inspect a DOM node, we currently serialize many properties for
that node, including its layout, computed style, used fonts, etc. Now
that we aren't piggy-backing on the Inspector interface, we can instead
only serialize the specific information required by DevTools.

Libraries/LibWebView/DOMNodeProperties.cpp

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2025, Tim Flynn <trflynn89@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibIPC/Decoder.h>
+#include <LibIPC/Encoder.h>
+#include <LibWebView/DOMNodeProperties.h>
+
+template<>
+ErrorOr<void> IPC::encode(Encoder& encoder, WebView::DOMNodeProperties const& attribute)
+{
+    TRY(encoder.encode(attribute.type));
+    TRY(encoder.encode(attribute.properties));
+    return {};
+}
+
+template<>
+ErrorOr<WebView::DOMNodeProperties> IPC::decode(Decoder& decoder)
+{
+    auto type = TRY(decoder.decode<WebView::DOMNodeProperties::Type>());
+    auto properties = TRY(decoder.decode<JsonValue>());
+
+    return WebView::DOMNodeProperties { type, move(properties) };
+}