1. Optimized the issue of low firepower coverage of the prop "scattered bullets" and almost empty bullets when attacking bosses
2. Fixed an error in the game where the default selected option changed due to input caching when the interface popped up after death
3. Added challenge mode (the mode selection interface is open after players complete any difficulty level):
- In challenge mode, players can only withstand damage from barrage or enemy once per life
- In challenge mode, the yellow line boundary for absorbing points/props above has been increased
- In challenge mode, when the score reaches a certain amount during the settlement of each level, an additional reward of one life will be given