See if we can improve the loop on the Etecoons' Cry sample

[CPColin]

In #717, I figured out a loop point for the Etecoons' Cry sample by trial and error. I didn't trim anything off the end, so the sample volume nears zero before looping to a louder part. As a result, it sounds like somebody cranked the SPC700's echo buffer to the max. This is probably good enough, but we could see if we can find a way to improve the sound.

We'll need a quicker way to test loop points, though. It could be neat to make a script that takes three ROM addresses (start, end, and loop) and decompresses and plays the resulting sample like the SPC700 would. Or this might be ridiculous overthinking of the problem. Find out which, because it could be fun!

[CPColin]

It was indeed ridiculous, but also fun:

https://github.com/CPColin/brr-script/blob/main/brr.main.kts

Now to see if some values sound better than others.