refactor: 清理代码，移除测试代码，更新版本号至 0.5.0

Author: nanbert

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "tank_battle"
-version = "0.3.0"
+version = "0.5.0"
 edition = "2024"
 
 [lib]

Cargo.toml

@@ -146,7 +146,6 @@ fn register_stage_intro_systems(app: &mut App) {
                 .run_if(|stage_level: Res<crate::resources::StageLevel>| stage_level.0 > 1),
             player::reset_player_positions,
             enemy::reset_enemy_spawn_state,
-            powerup::spawn_test_powerup, // 测试用：第一关强制生成 air_cushion 道具
         )
             .chain(),
     )

src/app.rs

@@ -43,9 +43,7 @@ pub struct ComboEvent {
 }
 
 /// 子弹资源缓存
-
 /// 用于预加载子弹纹理和音效，避免重复加载
-
 /// 子弹实体标记组件（包含所有者信息）
 
 #[derive(Component, Copy, Clone)]

src/bullet.rs

@@ -60,17 +60,12 @@ impl Default for GlobalRng {
 }
 
 /// 插件：注册全局随机数生成器
+#[derive(Default)]
 pub struct GlobalRngPlugin {
     /// 种子，None 表示使用默认固定种子
     pub seed: Option<u64>,
 }
 
-impl Default for GlobalRngPlugin {
-    fn default() -> Self {
-        Self { seed: None }
-    }
-}
-
 impl Plugin for GlobalRngPlugin {
     fn build(&self, app: &mut App) {
         let rng = match self.seed {