fix: 修复训练模式手牌显示不完整的问题

- 添加 ScrollContainer 包裹 HandArea，支持横向滚动查看所有27张牌
- HandArea 设置最小宽度 2200px 确保所有卡牌有足够空间
- 调整布局适配 1280x720 视口
- 按钮居中排列
- 清除调试 print 语句

🤖 Generated with [Qoder][https://qoder.com]

src/ui/components/hand_area.gd

@@ -13,7 +13,6 @@ const CARD_SCENE := preload("res://src/ui/components/card_node.tscn")
 var training_controller: TrainingController = null
 
 func update_hand(hand: Array) -> void:
-    print("[DEBUG] HandArea.update_hand called, cards count: ", hand.size())
     for cn in card_nodes:
         cn.queue_free()
     card_nodes.clear()
@@ -21,14 +20,12 @@ func update_hand(hand: Array) -> void:
     for c in hand:
         var node := CARD_SCENE.instantiate() as CardNode
         if node == null:
-            print("[DEBUG] CardNode instantiate returned null!")
             continue
         add_child(node)
         node.setup(c)
         node.card_clicked.connect(_on_card_clicked)
         node.card_double_clicked.connect(_on_card_double_clicked)
         card_nodes.append(node)
-    print("[DEBUG] CardNodes created: ", card_nodes.size())
 
 func _on_card_clicked(card_node: CardNode) -> void:
     card_node.set_selected(not card_node.is_selected)

src/ui/scenes/training_room.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=3 format=3 uid="uid://training_room"]
+[gd_scene load_steps=4 format=3 uid="uid://training_room"]
 
 [ext_resource type="Script" path="res://src/ui/scenes/training_room.gd" id="1_script"]
 
@@ -11,7 +11,7 @@ script = ExtResource("1_script")
 
 [node name="StatusLabel" type="Label" parent="."]
 layout_mode = 0
-offset_right = 400.0
+offset_right = 1280.0
 offset_bottom = 40.0
 text = "掼蛋训练模式"
 horizontal_alignment = 1
@@ -19,30 +19,41 @@ horizontal_alignment = 1
 [node name="GuideLabel" type="Label" parent="."]
 layout_mode = 0
 offset_top = 45.0
-offset_right = 800.0
+offset_right = 1280.0
 offset_bottom = 75.0
 text = "提示：点击手牌选中，然后点击「出牌」或「过牌」。首次出牌建议点击「提示」按钮。"
 horizontal_alignment = 1
 autowrap_mode = 2
 
-[node name="HandArea" type="HBoxContainer" parent="."]
+[node name="ScrollContainer" type="ScrollContainer" parent="."]
 layout_mode = 0
-offset_top = 500.0
-offset_right = 800.0
-offset_bottom = 650.0
+offset_top = 380.0
+offset_right = 1280.0
+offset_bottom = 520.0
+horizontal_scroll_mode = 2
+vertical_scroll_mode = 0
+
+[node name="HandArea" type="HBoxContainer" parent="ScrollContainer"]
+layout_mode = 2
+size_flags_horizontal = 0
 script = ExtResource("2_script")
+custom_minimum_size = Vector2(2200, 140)
 
 [node name="Buttons" type="HBoxContainer" parent="."]
 layout_mode = 0
-offset_top = 660.0
-offset_right = 800.0
-offset_bottom = 720.0
+offset_top = 540.0
+offset_right = 1280.0
+offset_bottom = 600.0
+alignment = 1
 
 [node name="PlayButton" type="Button" parent="Buttons"]
 text = "出牌"
+custom_minimum_size = Vector2(100, 40)
 
 [node name="PassButton" type="Button" parent="Buttons"]
 text = "过牌"
+custom_minimum_size = Vector2(100, 40)
 
 [node name="HintButton" type="Button" parent="Buttons"]
 text = "提示"
+custom_minimum_size = Vector2(100, 40)