In-game rule edit dialog

core/src/mindustry/game/Gamemode.java

@@ -13,6 +13,7 @@ public enum Gamemode{
     }, map -> map.spawns > 0),
     sandbox(rules -> {
         rules.infiniteResources = true;
+        rules.allowEditRules = true;
         rules.waves = true;
         rules.waveTimer = false;
     }),

core/src/mindustry/game/Rules.java

@@ -19,6 +19,8 @@ import mindustry.world.blocks.*;
  * Does not store game state, just configuration.
  */
 public class Rules{
+    /** Allows editing the rules in-game. Essentially a cheat mode toggle. */
+    public boolean allowEditRules = false;
     /** Sandbox mode: Enables infinite resources, build range and build speed. */
     public boolean infiniteResources;
     /** Team-specific rules. */