feat: 实现时间流动完整逻辑并同步 HUD 显示

- TimeSystem 支持月/年进位，仅游戏场景推进
- HUD 时间标签订阅 day_passed 实时更新
- 新游戏时重置年月日

src/UI/HUD/TopBarHUD.tscn

@@ -5,6 +5,7 @@
 
 [sub_resource type="LabelSettings" id="LabelSettings_bn2o5"]
 font = ExtResource("1_pa2rn")
+font_size = 32
 
 [node name="TopBarHud" type="Control" unique_id=1115394694]
 layout_mode = 3
@@ -46,6 +47,7 @@ label_settings = SubResource("LabelSettings_bn2o5")
 layout_mode = 2
 size_flags_horizontal = 3
 size_flags_vertical = 8
+size_flags_stretch_ratio = 2.0
 label_settings = SubResource("LabelSettings_bn2o5")
 
 [node name="Label_Reputation" type="Label" parent="HBoxContainer" unique_id=985110673]