Change black empty tile to grass and make it destructable

src/engine/simulation/simulation.ts

@@ -1,6 +1,7 @@
 import type { World, EntityId, Action, SimEvent, Actor, CombatantActor, CollectibleActor, ActorType } from "../../core/types";
 
-import { isBlocked, inBounds, isWall } from "../world/world-logic";
+import { isBlocked, inBounds, isWall, tryDestructTile } from "../world/world-logic";
+import { isDestructibleByWalk } from "../../core/terrain";
 import { findPathAStar } from "../world/pathfinding";
 import { GAME_CONFIG } from "../../core/config/GameConfig";
 import { type EntityManager } from "../EntityManager";
@@ -105,6 +106,16 @@ function handleMove(w: World, actor: Actor, action: { dx: number; dy: number },
     const to = { ...actor.pos };
     const events: SimEvent[] = [{ type: "moved", actorId: actor.id, from, to }];
     
+    // Check for "destructible by walk" tiles (e.g. grass)
+    // We check the tile at the *new* position
+    const tileIdx = ny * w.width + nx;
+    const tile = w.tiles[tileIdx];
+    if (isDestructibleByWalk(tile)) {
+      tryDestructTile(w, nx, ny);
+      // Optional: Add an event if we want visual feedback immediately,
+      // but the renderer usually handles map updates automatically or next frame
+    }
+
     if (actor.category === "combatant" && actor.isPlayer) {
       handleExpCollection(w, actor, events, em);
     }