fix: 修复欢迎板和通知板通知无法关闭问题

- 修复欢迎板和通知板当前被ChatUI 抢占鼠标问题，通过设置启动弹窗时ChatUI 根节点 mouse_filter 临时改为 IGNORE来实现
- ToDo: 后续统一规划事件逻辑

scenes/Maps/square.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=39 format=4 uid="uid://5cc0c6cpnhe8"]
+[gd_scene load_steps=40 format=4 uid="uid://5cc0c6cpnhe8"]
 
 [ext_resource type="Script" uid="uid://b43tvo8cykfrq" path="res://scenes/Maps/BaseLevel.gd" id="1_m4als"]
 [ext_resource type="Texture2D" uid="uid://baa5wkuyqouh6" path="res://assets/sprites/environment/standard_brick_128_128.jpg" id="1_rb5kq"]
@@ -18,6 +18,7 @@
 [ext_resource type="PackedScene" uid="uid://c7k8yay002w4" path="res://scenes/prefabs/items/welcome_board.tscn" id="16_edt5w"]
 [ext_resource type="PackedScene" uid="uid://bvfyllcy5fi8o" path="res://scenes/Maps/datawhale_home.tscn" id="16_m4als"]
 [ext_resource type="PackedScene" uid="uid://rdmrm7j4iokr" path="res://scenes/prefabs/items/notice_board.tscn" id="16_rixdf"]
+[ext_resource type="Script" uid="uid://d2od22agputjt" path="res://scenes/prefabs/items/WelcomeBoard.gd" id="16_u1t8b"]
 [ext_resource type="Script" uid="uid://rlkavptfhr4y" path="res://scenes/Maps/DoorTeleport.gd" id="18_0xqio"]
 
 [sub_resource type="TileSetAtlasSource" id="TileSetAtlasSource_7nixu"]
@@ -1086,6 +1087,7 @@ position = Vector2(-184, -76)
 z_index = 1
 y_sort_enabled = true
 position = Vector2(128, -80)
+script = ExtResource("16_u1t8b")
 
 [node name="DefaultSpawn" type="Marker2D" parent="."]
 y_sort_enabled = true