Fix script.txt format to match SpringBoard's script generator

Based on actual SpringBoard code analysis:

save_project_info_command.lua:109-126 creates a script table:
  mapSeed = project.randomMapOptions.mapSeed,  (top level)
  mapOptions = {
      new_map_x = ...,
      new_map_y = ...
  },

StartScript.GenerateScriptTxt() converts this to:
  [MAPOPTIONS] { new_map_x=...; new_map_y=...; }
  [MODOPTIONS] { mapseed=...; }

Note: 'mapseed' is lowercase in generated files (_script.txt line 25)

The script needs BOTH sections:
- [MAPOPTIONS] for map dimensions
- [MODOPTIONS] for map seed

This matches the format in test-engine/test-data/_script.txt

Author: claude

test-smoke.sh

@@ -65,6 +65,10 @@ cat > script.txt << 'EOF'
     new_map_x=10;
     new_map_y=8;
   }
+  [MODOPTIONS]
+  {
+    mapseed=1;
+  }
   [PLAYER0]
   {
     Name=TestPlayer;