handle the main function for sdl correctly as the docs say

SakuraVNE/src/main.cpp

@@ -1,8 +1,11 @@
-#define SDL_MAIN_HANDLED
+#define SDL_MAIN_HANDLED 1
 
 #include "Application.h"
+#include "SDL3/SDL_main.h"
 
 int main(int argc, char *argv[]) {
+    SDL_SetMainReady();
+
     Application app;
 
     bool success = app.Init();