Adding flying functionality for enemies

Assets/_Project/Scripts/Gameplay/LevelLoader.cs

@@ -316,6 +316,23 @@ namespace TD.Gameplay
             return runtimeWalkability[idx];
         }
 
+        /// <summary>
+        /// True if <paramref name="tile"/> is walkable in the BAKED terrain grid, ignoring
+        /// any runtime tower placement. Returns false for out-of-bounds tiles.
+        /// </summary>
+        /// <remarks>
+        /// Flying enemies path against this grid so they soar over towers (which only
+        /// affect <see cref="IsWalkable"/>'s runtime grid) while still respecting
+        /// impassable terrain and map bounds. Because the baked grid never changes at
+        /// runtime, flying paths are computed once and never need invalidation.
+        /// </remarks>
+        public bool IsBaseWalkable(Vector2Int tile)
+        {
+            if (level == null || level.WalkabilityGrid == null) return false;
+            if (!TryFlatIndex(tile, out int idx)) return false;
+            return level.WalkabilityGrid[idx];
+        }
+
         /// <summary>
         /// Placement state for <paramref name="tile"/>. Returns
         /// <see cref="PlacementState.Outside"/> for out-of-bounds tiles.