In-game campaign, map and block script editors

Mission graph with branches, mission settings and goals, map editor on the
3D view (terrain, places, units, towers, traps, forts, rivals, zones; undo,
brush, rectangle, fill, mirror), block editor with palette, nesting, live
problems, undo, copy/paste and search; test play with a script debug view;
demo campaign and built-in missions as templates.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/map.rs

@@ -16,7 +16,7 @@ thread_local! {
     static DIMS: Cell<(usize, usize)> = Cell::new((64, 64));
 }
 
-fn set_dims(w: usize, h: usize) {
+pub fn set_dims(w: usize, h: usize) {
     DIMS.with(|d| d.set((w, h)));
 }
 #[inline]