Match loop on the client side: orders go to the server, a confirmed turn steps the world five times, and a checksum of the shared state catches worlds that diverge

src/main.rs

@@ -13,6 +13,7 @@ mod gfx;
 mod i18n;
 mod map;
 mod menu;
+mod netplay;
 mod personality;
 mod platform;
 mod orders;