Wrong BGM in OG BGM mode near start of game

Note: GIN is intending to check/fix this together with all the question arcs BGM script changes. I'm just recording this so we don't forget it later.

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At the start of tatari, `lsys28` plays.

In "normal BGM/Mangagamer BGM mode, we play: https://www.youtube.com/watch?v=XR2R3eIHbts&t=335s (we don't want to change this - I've just provided it for comparison). This is what Mangagamer provides for `lsys28`

When using the OG BGM, we currently play: https://www.youtube.com/watch?v=DatdHJym3Cg

However, in the original game, the song "LOOP131" plays: https://youtu.be/TT2R86jbw4k&t=602 / https://www.youtube.com/watch?v=bPdUNFWLnzU&t=1587s

A helpful reddit comment pointed me to this:

> It depends on which version you played. The original Japanese version used a short loop called 人食い族 ("Cannibal Tribe", filename "LOOP131.wav") by AIDIA, but the old Mangagamer translation and the post-2019 Steam version each replaced it with tracks of unknown origin, possibly custom-made for those versions.

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We should change either change the OG BGM's `lsys28` to LOOP131, or change the script to play LOOP131 just for this instance, depending on what is more correct.

Also see https://github.com/07th-mod/meakashi/issues/68 "Some BGM/sound effect versions are inconsistent with the question arcs", which I think has been resolved already. Once work starts on BGM stuff, we should make a indexing issue which links to all the other BGM issues.

@GIN5

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Here is the LOOP131.WAV from the original game that we want to include in the mod:
[LOOP131.zip](https://github.com/07th-mod/tatarigoroshi/files/6873221/LOOP131.zip)

The issue is about a specific BGM track (lsys28) playing incorrectly in OG BGM mode at the start of the game. The correct track is LOOP131.wav, which is provided as a zip attachment. First, locate the BGM script or configuration files that handle lsys28 mapping for OG BGM mode. Compare with the normal BGM mode to understand the current setup. Then, either change the mapping for lsys28 to LOOP131 or adjust the script to play LOOP131 for this instance, ensuring consistency with the original game. Test the change by running the game from the start of tatari to verify the correct track plays.

Written by the indexing model from the issue text.