feat(武器系统): 为BigLaser武器添加执行伤害和升华选项

- 在ObstacleBase和EntityBase中添加getHealthPercent方法用于获取生命值百分比
- 修改bulletHit方法支持伤害覆盖参数
- 为BigLaser武器添加5个升华选项，包括临界斩杀效果
- 实现damageOverride方法根据目标生命值动态调整伤害
- 修复store数值可能为负数的问题

scripts/Structs/Weapon.gd

@@ -241,7 +241,7 @@ func rebuildSublimateOptions(showNext: bool):
 		sublimateOptionsBox.add_child(instance)
 	disruptSublimateOptions()
 func readStore(key: String):
-	return store.get(key, 0) + readStoreExtra(key)
+	return clamp(store.get(key, 0) + readStoreExtra(key), 0, INF)
 func playSound(sound: String):
 	var body = sounds.get_node_or_null(sound)
 	if body is AudioStreamPlayer2D:
@@ -284,7 +284,6 @@ func addStoreExtra(key: String, value: float):
 	if !storeExtra.has(key):
 		storeExtra[key] = 0
 	storeExtra[key] += value
-	storeExtra[key] = clamp(storeExtra[key], 0, INF)
 func readStoreExtra(key: String):
 	return storeExtra.get(key, 0)
 func getSublimateOptions() -> Array[SublimateOption]: