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/ai.rs

@@ -99,6 +99,7 @@ impl Game {
                         continue;
                     }
                     self.map.t[i].marked = true;
+                    self.map.t[i].mark_by = self.me.side().min(7);
                     added += 1;
                 }
             }
@@ -150,6 +151,7 @@ impl Game {
             let t = self.map.t[i];
             if t.diggable() && !t.plant() && t.kind != Kind::Steel && (t.owner == Owner::None || t.owner == me || t.reinforced) {
                 self.map.t[i].marked = true;
+                self.map.t[i].mark_by = self.me.side().min(7);
                 if t.vein().is_some() {
                     cluster.push(i);
                 }
@@ -162,6 +164,7 @@ impl Game {
                 if let Some(t) = self.map.get(x + dx, y + dy) {
                     if t.vein().is_some() && t.owner == Owner::None {
                         self.map.t[idx(x + dx, y + dy)].marked = true;
+                        self.map.t[idx(x + dx, y + dy)].mark_by = self.me.side().min(7);
                     }
                 }
             }