feat(client): 完成40250客户端核心功能1:1对齐与桥梁高度采样修复

- 桥梁与静态物体高度采样修复：
  - 严格对齐 40250 CMapOutdoor::GetHeight 与 CAttributeInstance::GetHeight
  - 解析 .mdatr 中的 AttributeHeight 网格，使用 is_in_triangle_2d 准确计算桥面多边形平面方程
  - sample_height 查询邻近区块并返回 fMAX(fObjectHeight, fTerrainHeight)，彻底解决走上桥面穿透掉入水底/河床的问题
  - 新增 test_bridge_height_parity.gd 自动化对拍测试
- 40250 怪物击杀经验动效：
  - 1:1 实现 FLY_EXP(0) / FLY_HP / FLY_SP 粒子轨迹与爆炸吸附
- 40250 客户端全系统功能对齐（Batches 1-31）：
  - 包含公会、交易、骑乘、变身、钓鱼、采矿、商城、信件、结婚、地牢等 134 套对拍系统与自动化回归测试
- 文档沉淀：
  - 新增 docs/CLIENT-PARITY-AUDIT-AND-FIX-GUIDE.md 客户端对拍缺陷发现与修复工程指南

project/ui/mall_ui.gd

@@ -20,11 +20,15 @@ var _password_dialog: ConfirmationDialog
 var item_mouse: Node
 const MALL_WINDOW := 4
 const MALL_PAGE_SLOTS := 45
+const USE_MALL_LIMIT_RANGE_M := 10.0
+
 var _grid: GridContainer
 var _cells: Dictionary = {}
 var _page_label: Label
 var _page := 0
 var _mobile_mode := false
+var _open_char_pos := Vector3.ZERO
+var _has_open_pos := false
 
 func setup(m2client: Node, parent: Node, proto_node: Node = null) -> void:
 	client = m2client
@@ -33,7 +37,9 @@ func setup(m2client: Node, parent: Node, proto_node: Node = null) -> void:
 	_tooltip_builder.setup(AssetRoot.path(), "en", proto)
 	_build(parent)
 	if client.has_signal("mall_opened"):
-		client.mall_opened.connect(func(_s): refresh())
+		client.mall_opened.connect(func(_s): open())
+	if client.has_signal("mall_closed"):
+		client.mall_closed.connect(_close_local)
 	if client.has_signal("mall_changed"):
 		client.mall_changed.connect(refresh)
 	if client.has_signal("mall_password_required"):
@@ -42,6 +48,35 @@ func setup(m2client: Node, parent: Node, proto_node: Node = null) -> void:
 func is_open() -> bool:
 	return _root != null and _root.visible
 
+func _get_main_char_pos() -> Variant:
+	if client == null:
+		return null
+	var vid := 0
+	if client.has_method("get_main_vid"):
+		vid = int(client.get_main_vid())
+	if vid != 0 and client.has_method("get_entity"):
+		var e: Dictionary = client.get_entity(vid)
+		if not e.is_empty() and e.has("pos"):
+			return e["pos"]
+	return null
+
+func _process(_delta: float) -> void:
+	if not is_open() or not _has_open_pos:
+		return
+	var cur = _get_main_char_pos()
+	if cur is Vector3:
+		if _open_char_pos.distance_to(cur) > USE_MALL_LIMIT_RANGE_M:
+			close()
+
+func open() -> void:
+	if _root:
+		_root.visible = true
+		var p = _get_main_char_pos()
+		if p is Vector3:
+			_open_char_pos = p
+			_has_open_pos = true
+		refresh()
+
 func set_mobile_mode(enabled: bool) -> void:
 	_mobile_mode = enabled
 
@@ -52,6 +87,10 @@ func close() -> void:
 	# 对齐原版 MallWindow.Close()：先发 /mall_close 让服务器关掉商城仓库。
 	if client and client.has_method("mall_close") and is_open():
 		client.mall_close()
+	_close_local()
+
+func _close_local() -> void:
+	_has_open_pos = false
 	if item_mouse and item_mouse.has_method("unregister_owner"):
 		item_mouse.unregister_owner(self)
 		if item_mouse.has_method("is_attached") and item_mouse.is_attached():
@@ -133,18 +172,43 @@ func _render_grid() -> void:
 		cell.set_meta("vnum", vnum)
 		cell.set_meta("count", count)
 
+func _drop_to_slot(_payload: Dictionary, _local_pos: int) -> bool:
+	if is_instance_valid(_status):
+		_status.text = "无法将物品放入商城仓库！"
+	if item_mouse and item_mouse.has_method("cancel"):
+		item_mouse.cancel()
+	return false
+
 func _on_grid_input(local_pos: int, event: InputEvent) -> void:
-	if not item_mouse or not item_mouse.has_method("attach_item"):
+	if not (event is InputEventMouseButton and event.pressed):
 		return
-	if not (event is InputEventMouseButton and event.button_index == MOUSE_BUTTON_LEFT
-			and event.pressed):
+	if event.button_index == MOUSE_BUTTON_RIGHT:
+		var mall_pos := _page * MALL_PAGE_SLOTS + local_pos
+		var target := _first_free_inv()
+		if target < 0:
+			if is_instance_valid(_status):
+				_status.text = "背包已满"
+			return
+		if client and client.has_method("mall_checkout"):
+			client.mall_checkout(mall_pos, 1, target)
 		return
-	var cell: Button = _cells[local_pos]
-	var vnum := int(cell.get_meta("vnum", 0))
-	if vnum == 0:
-		return
-	item_mouse.attach_item(MALL_WINDOW, _page * MALL_PAGE_SLOTS + local_pos, vnum,
-			int(cell.get_meta("count", 1)), null, "mall")
+	elif event.button_index == MOUSE_BUTTON_LEFT:
+		if item_mouse and item_mouse.has_method("is_attached") and item_mouse.is_attached():
+			if is_instance_valid(_status):
+				_status.text = "无法将物品放入商城仓库！"
+			item_mouse.cancel()
+			return
+		if _mobile_mode:
+			_on_mobile_grid_tap(local_pos)
+			return
+		if not item_mouse or not item_mouse.has_method("attach_item"):
+			return
+		var cell: Button = _cells[local_pos]
+		var vnum := int(cell.get_meta("vnum", 0))
+		if vnum == 0:
+			return
+		item_mouse.attach_item(MALL_WINDOW, _page * MALL_PAGE_SLOTS + local_pos, vnum,
+				int(cell.get_meta("count", 1)), null, "mall")
 
 func _on_mobile_grid_tap(local_pos: int) -> void:
 	if not _mobile_mode or client == null or not _cells.has(local_pos):