[feat] add CrossDesk MCP with remote desktop panels

libs/controller/include/frame_image.h

@@ -0,0 +1,27 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2026-11-02
+ * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _FRAME_IMAGE_H_
+#define _FRAME_IMAGE_H_
+
+#include <controller_session.h>
+
+namespace crossdesk {
+struct ImageRegion {
+  int x = 0, y = 0, width = 0, height = 0;
+};
+struct FrameImage {
+  int width = 0, height = 0;
+  ImageRegion region;
+  std::vector<uint8_t> png;
+};
+// Pure bounded conversion; safe on an encoding worker, never calls the session.
+FrameImage EncodeFrameImage(const DecodedFrame &frame, ImageRegion region,
+                            int max_edge, size_t max_bytes);
+std::string ImageBase64(const std::vector<uint8_t> &bytes);
+} // namespace crossdesk
+
+#endif