[feat] add remote display resolution selection to video settings

libs/wire/include/display_resolution.h

@@ -0,0 +1,65 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2026-11-11
+ * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _DISPLAY_RESOLUTION_H_
+#define _DISPLAY_RESOLUTION_H_
+
+#include <algorithm>
+#include <cstdint>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace crossdesk {
+
+inline constexpr int kMaxResolutionDisplays = 32;
+inline constexpr int kMaxDisplayResolutionModes = 256;
+
+struct DisplayResolution {
+  int width = 0;
+  int height = 0;
+  bool operator==(const DisplayResolution &other) const {
+    return width == other.width && height == other.height;
+  }
+};
+
+inline bool ValidDisplayResolution(const DisplayResolution &mode) {
+  return mode.width > 0 && mode.height > 0 && mode.width <= 32768 &&
+         mode.height <= 32768;
+}
+
+struct DisplayResolutionInfo {
+  int display_id = 0;
+  // Opaque native identity: reject requests for a replaced/hot-unplugged
+  // screen.
+  std::string display_key;
+  DisplayResolution current;
+  std::vector<DisplayResolution> modes;
+  bool operator==(const DisplayResolutionInfo &other) const {
+    return display_id == other.display_id && display_key == other.display_key &&
+           current == other.current && modes == other.modes;
+  }
+};
+
+struct DisplayResolutionChange {
+  int display_id = 0;
+  std::string display_key;
+  DisplayResolution resolution;
+  uint32_t request_id = 0;
+  bool accepted = false;
+};
+
+inline bool SupportsDisplayResolution(const DisplayResolutionInfo &display,
+                                      const DisplayResolutionChange &change) {
+  return display.display_id == change.display_id &&
+         display.display_key == change.display_key &&
+         std::find(display.modes.begin(), display.modes.end(),
+                   change.resolution) != display.modes.end();
+}
+
+} // namespace crossdesk
+
+#endif

libs/wire/include/remote_action.h

@@ -13,6 +13,7 @@
 #include <vector>
 
 #include <remote_cursor_shape.h>
+#include <display_resolution.h>
 
 namespace crossdesk {
 
@@ -33,6 +34,8 @@ enum ControlType {
   video_settings_status = 12,
   text_input = 13,
   video_codec_status = 14,
+  display_resolution = 15,
+  display_resolution_status = 16,
 };
 
 enum MouseFlag {
@@ -217,6 +220,9 @@ struct RemoteAction {
 
   // Committed UTF-8 text. Kept outside the POD union for automatic ownership.
   std::string text;
+  // Optional host information extension, also returned with resolution status.
+  std::vector<DisplayResolutionInfo> display_resolutions;
+  DisplayResolutionChange resolution_change;
 
   std::string to_json() const;
   bool from_json(const std::string& json_string);