launcher: configure and preview DualSense lightbar color (#912)

launcher: configure and preview controller lightbar color

Add an optional lightbar color to launcher settings and pass it to the emulator with --controller-color. Preview changes on RGB gamepads, handle controller hotplug events, and restore the saved color when settings dialogs close. Release launcher preview handles when starting a game.

Co-authored-by: m66401970-eng <m66401970@gmail.com>

src/common/emulatorConfig.h

@@ -4,7 +4,9 @@
 #include "common/common.h"
 
 #include <cstddef>
+#include <array>
 #include <filesystem>
+#include <optional>
 #include <string>
 #include <vector>
 
@@ -26,6 +28,7 @@ enum class LogDirection { Silent, Console, File };
 enum class PresentMode { Fifo, Mailbox, Immediate };
 
 using Keymap = std::vector<std::string>;
+using ControllerColor = std::array<uint8_t, 3>;
 
 constexpr uint32_t DEFAULT_CONSOLE_LANGUAGE = 1;
 constexpr uint32_t MAX_CONSOLE_LANGUAGE     = 29;
@@ -44,6 +47,7 @@ struct ConfigOptions {
 	std::string            user_name                   = "Kyty";
 	int32_t                user_id                     = DEFAULT_USER_ID;
 	std::string            audio_input_device;
+	std::optional<ControllerColor> controller_color;
 	PresentMode            present_mode                = PresentMode::Mailbox;
 	int32_t                gpu_index                   = -1;
 	bool                   fullscreen_enabled          = false;
@@ -81,6 +85,7 @@ uint32_t GetScreenHeight();
 const std::string& GetUserName();
 int32_t  GetUserId();
 const std::string& GetAudioInputDevice();
+const std::optional<ControllerColor>& GetControllerColor();
 PresentMode GetPresentMode();
 int32_t GetGpuIndex();
 bool     FullscreenEnabled();