ToaHartor/GI-cutscenes — reverse-engineered prompt

Build me a command line tool for Genshin Impact cutscene files. I want to point it at one USM file or a whole folder of USM files, then have it extract the video and audio, decrypt what it can, convert the audio into normal WAV files, and optionally merge everything into a playable MKV movie.

It should support subtitles from the game data folder, convert them into a format that looks right in the final video, and let me include fonts if I put them next to the tool. I’d like simple commands for single file extraction, batch extraction, HCA to WAV conversion, updating the version keys file, and resetting the config.

Please make it a .NET 6 C# console app with clear help text, a sample appsettings file for ffmpeg, mkvmerge, subtitle folder, and subtitle style, and sensible errors when keys or files are missing. Also include options for output folder, keeping extracted files, merge engine, audio and video formats, and choosing audio languages like Chinese, English, Japanese, and Korean.