1. Optimized the "Unlock Difficulty" function, which now saves the difficulty
2. Removed the function of "unlock all" (there will be many bugs, it is recommended to use the other three unlocks, the effect is the same)

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1.优化了“解锁难度”的功能，现在会对难度进行保存
2.删除了“解锁全部”的功能（会有很多BUG，建议使用其他三个解锁，效果一致）

Fix "Unlock All" Bug

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修复了”解锁全部“的Bug