Dig marks in the colour of the master who set them; every master's dungeon is lit

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

src/game.rs

@@ -4853,6 +4853,7 @@ impl Game {
                     let t = &mut self.map.t[idx(x, y)];
                     if t.diggable() {
                         t.marked = on;
+                        t.mark_by = self.me.side().min(7);
                     }
                 }
             }