Redundant files in classic BGM pack for question arcs

The question arcs' classic BGM pack contains a huge amount of files that are completely identical with the files from MangaGamer's current soundtrack, particularly most of the lsys files and MIDI conversions.

Unless you want your patches to be compatible with outdated vanilla versions, these are completely pointless, seeing how they just replace identical files.

检查问题篇的经典 BGM 包，以识别与 MangaGamer 原声带重复的冗余文件。查看文件结构并比较 lsys 和 MIDI 文件。确定哪些文件可以安全移除，且不会破坏旧版本的兼容性。检查补丁编译器对 BGM 资源的处理方式，以了解其影响。

由索引模型根据 Issue 内容生成。