feat: 新增 TimeSystem 时间系统并注册 Autoload

- project.godot 注册 GameState/TimeSystem 单例
- 存档面板新增快速存档按钮组
- 新增 export_presets.cfg 导出配置

src/Core/TimeSystem.gd

@@ -0,0 +1,18 @@
+extends Node
+
+signal day_passed(year, month, day)
+
+const DAY_LENGTH := 5.0
+var speed := 1.0
+var _elapsed := 0.0
+
+func _process(delta: float) -> void:
+	_elapsed += delta * speed
+	if _elapsed >= DAY_LENGTH:
+		_elapsed -= DAY_LENGTH
+		_advance()
+
+func _advance() -> void:
+	# GameState.year, GameState.month, GameState.day 推进
+	GameState.day = GameState.day + 1;
+	day_passed.emit()

src/Core/TimeSystem.gd.uid

@@ -0,0 +1 @@
+uid://c13ljuiktgrgw

src/UI/Panels/SavePanel.tscn

@@ -36,11 +36,26 @@ layout_mode = 2
 size_flags_vertical = 3
 size_flags_stretch_ratio = 9.0
 
-[node name="SlotList" type="VBoxContainer" parent="VBoxContainer/ScrollContainer" unique_id=674823582]
+[node name="HBoxContainer" type="HBoxContainer" parent="VBoxContainer/ScrollContainer" unique_id=596966633]
+layout_mode = 2
+size_flags_horizontal = 3
+size_flags_vertical = 3
+
+[node name="VBoxContainer" type="VBoxContainer" parent="VBoxContainer/ScrollContainer/HBoxContainer" unique_id=844163531]
 layout_mode = 2
 size_flags_horizontal = 3
 
-[node name="SaveSlot" parent="VBoxContainer/ScrollContainer/SlotList" unique_id=214547620 instance=ExtResource("2_uloko")]
+[node name="SaveGroup" type="Button" parent="VBoxContainer/ScrollContainer/HBoxContainer/VBoxContainer" unique_id=150349711]
 layout_mode = 2
+text = "存档1"
+
+[node name="SlotList" type="VBoxContainer" parent="VBoxContainer/ScrollContainer/HBoxContainer" unique_id=674823582]
+layout_mode = 2
+size_flags_horizontal = 3
+size_flags_stretch_ratio = 5.0
+
+[node name="SaveSlot" parent="VBoxContainer/ScrollContainer/HBoxContainer/SlotList" unique_id=214547620 instance=ExtResource("2_uloko")]
+layout_mode = 2
+size_flags_vertical = 1
 
 [connection signal="button_up" from="VBoxContainer/Header/Button_Esc" to="." method="_on_button_esc_button_up"]