fix(BulletBase): 添加父节点有效性检查防止崩溃

在子弹分裂和折射时检查父节点是否有效，避免无效引用导致的崩溃

components/Characters/Rooster.tscn

@@ -2,7 +2,7 @@
 
 [ext_resource type="PackedScene" uid="uid://cvogxi7mktumf" path="res://components/Abstracts/EntityBase.tscn" id="1_e5pl8"]
 [ext_resource type="Script" uid="uid://cthtupc6dtbav" path="res://scripts/Contents/Characters/Rooster.gd" id="2_oqdqd"]
-[ext_resource type="PackedScene" uid="uid://dlaks67h2osms" path="res://components/Weapons/ChainGun.tscn" id="3_s7kxe"]
+[ext_resource type="PackedScene" uid="uid://c3crr8r7y3oho" path="res://components/Weapons/BlueCrystal.tscn" id="3_da2ca"]
 [ext_resource type="AudioStream" uid="uid://cdrevrq7n6yqa" path="res://resources/sounds/effect/Boing.mp3" id="4_66s6c"]
 [ext_resource type="AudioStream" uid="uid://benyec5bqni0b" path="res://resources/sounds/effect/Chomp.wav" id="4_k0yme"]
 [ext_resource type="AudioStream" uid="uid://dmxh3bpk8vyy5" path="res://resources/sounds/effect/Coin.mp3" id="5_xnbhq"]
@@ -58,8 +58,7 @@ metadata/_edit_vertical_guides_ = [71.0]
 [node name="weaponStore" parent="." index="1"]
 process_mode = 4
 
-[node name="ChainGun" parent="weaponStore" index="0" instance=ExtResource("3_s7kxe")]
-debugRebuild = false
+[node name="BlueCrystal" parent="weaponStore" index="0" instance=ExtResource("3_da2ca")]
 
 [node name="sprint" parent="sounds" index="0"]
 stream = ExtResource("4_66s6c")

scripts/Statemachine/BulletBase.gd

@@ -152,6 +152,7 @@ func trySplit():
 			cloned.rotation += deg_to_rad(360.0 / total * i + 180)
 			cloned.canDuplicateSelf = false
 			cloned.launcher = launcher
+			if is_instance_valid(parent):
 				cloned.parent = parent
 			get_parent().add_child.call_deferred(split(cloned, i, total, last))
 func tryRefract():
@@ -173,6 +174,7 @@ func tryRefract():
 				cloned.look_at(entity.position)
 				cloned.canDuplicateSelf = false
 				cloned.launcher = launcher
+				if is_instance_valid(parent):
 					cloned.parent = parent
 				get_parent().add_child.call_deferred(refract(cloned, entity, i, total, last))