death sounds, build sounds, better audio management

Assets/_Project/Scripts/Gameplay/TowerInstance.cs

@@ -166,6 +166,11 @@ namespace TD.Gameplay
             }
         }
 
+        // ----- Events ---------------------------------------------------------
+
+        /// <summary>Fired on ALL peers when this tower finishes construction and spawns.</summary>
+        public event System.Action OnBuiltClient;
+
         // ----- Server-only initialization -------------------------------------
 
         /// <summary>
@@ -262,6 +267,8 @@ namespace TD.Gameplay
                           $"for {ownerSlot.Value} at anchor {anchorTile.Value}. " +
                           $"IsServer={IsServer}");
             }
+
+            OnBuiltClient?.Invoke();
         }
 
         public override void OnNetworkDespawn()