Updating HUD, Gold Config, and finishing off Play flow for 9player map.

Assets/_Project/Scripts/Gameplay/LevelLoader.cs

@@ -1,4 +1,5 @@
 // Assets/_Project/Scripts/Gameplay/LevelLoader.cs
+using System.Collections.Generic;
 using UnityEngine;
 using TD.Core;
 using TD.Levels;
@@ -379,6 +380,12 @@ namespace TD.Gameplay
         /// <c>false</c>) and when a tower is sold/destroyed (pass <c>true</c>).
         /// No-ops silently for out-of-bounds tiles.
         /// </summary>
+        /// <remarks>
+        /// Fires <see cref="OnWalkabilityChanged"/> once if the tile actually changed.
+        /// For multi-tile stamps (a tower footprint), prefer
+        /// <see cref="SetWalkableBatch"/> to fire the event ONCE for the whole batch
+        /// instead of per-tile — every event triggers all enemy re-paths.
+        /// </remarks>
         public void SetWalkable(Vector2Int tile, bool walkable)
         {
             if (!TryFlatIndex(tile, out int idx)) return;
@@ -387,6 +394,28 @@ namespace TD.Gameplay
             OnWalkabilityChanged?.Invoke();
         }
 
+        /// <summary>
+        /// Batched variant of <see cref="SetWalkable"/>: updates every tile in
+        /// <paramref name="tiles"/> to <paramref name="walkable"/> and fires
+        /// <see cref="OnWalkabilityChanged"/> AT MOST ONCE for the entire batch
+        /// (only if at least one tile actually changed). Use this for tower footprint
+        /// stamps so a 2×2 placement triggers a single enemy re-path instead of four.
+        /// Out-of-bounds tiles in the list are skipped silently.
+        /// </summary>
+        public void SetWalkableBatch(IList<Vector2Int> tiles, bool walkable)
+        {
+            if (tiles == null) return;
+            bool anyChanged = false;
+            for (int i = 0; i < tiles.Count; i++)
+            {
+                if (!TryFlatIndex(tiles[i], out int idx)) continue;
+                if (runtimeWalkability[idx] == walkable) continue;
+                runtimeWalkability[idx] = walkable;
+                anyChanged = true;
+            }
+            if (anyChanged) OnWalkabilityChanged?.Invoke();
+        }
+
         /// <summary>
         /// Sets the runtime occupancy of <paramref name="tile"/>. Called alongside
         /// <see cref="SetWalkable"/> — always update both grids together so they