Add Lua scripting support to desktop emulator

- Created emulator-specific lua_game_emulator.cpp using filesystem instead of FatFS
- Created lua_game_loader_emulator.cpp to scan games/lua_examples directory
- Updated CMakeLists.txt to include Lua 5.4 engine and bindings
- Updated to SFML 3.0 API compatibility (event handling, sprite initialization)
- Updated Game class to use public members for Lua bindings
- Updated GameLauncher to use std::function for lambda captures
- Added continuous 60 FPS rendering for smooth display
- Emulator now loads and runs all three example Lua games

emulator/game.h

@@ -15,7 +15,8 @@ public:
     virtual bool update(const InputEvent& event) = 0;
     virtual void draw() = 0;
     virtual bool wants_to_exit() const { return false; }
-protected:
+    
+    // Public members for Lua bindings access
     uint16_t width;
     uint16_t height;
     LowLevelRenderer* renderer;