feat: major engine overhaul - scene demo with lighting, sphere, ground

- Scene Demo: cube + sphere + ground plane with proper lighting
- Audio: XAudio2 dynamic loading + WAV playback
- Physics: expanded collision system
- Renderer: improved pipeline with materials
- UI: extended widget system
- VisualScript: enhanced serializer + block interactions
- ASM: optimized math/memory/profiling routines
- Window: mouse input + scroll support

Demo/editor_main.c

@@ -142,8 +142,8 @@ static void on_mouse_move(int x, int y) {
     g_mouse_x = x; g_mouse_y = y;
 }
 
-static void on_mouse_button(int button) {
-    if (button == 0) {
+static void on_mouse_button(int button, int pressed) {
+    if (button == 0 && pressed) {
         if (g_mouse_click == 0) {
             g_mouse_click = 1;
             g_mouse_click_x = g_mouse_x;