(client) feat:右键菜单全局与UI分离，Building生成支持，双层地图重写

Client/Assets/Scripts/UI/EntityPlacementUI.cs

@@ -13,6 +13,9 @@ namespace UI
         
         public NonReturnCallback currentAction;
 
+        public GameObject focusBox;
+        public bool snapEnabled = false;
+
         public string Prompt
         {
             get => promptText.text;
@@ -30,7 +33,28 @@ namespace UI
             {
                 currentAction();
             }
+
+            if (snapEnabled)
+            {
+                focusBox.transform.position = Utils.MousePosition.GetSnappedWorldPosition();
+            }
+            else
+            {
+                focusBox.transform.position = Utils.MousePosition.GetWorldPosition();
+            }
+
+        }
+
+        public override void Show()
+        {
+            base.Show();
+            focusBox.SetActive(true);
+        }
+
+        override public void Hide()
+        {
+            base.Hide();
+            focusBox.SetActive(false);
         }
-        
     }
 }