[Tech debt] Automate/improve tooling for generation of beta client data files

[fribbels]

Motivation

Currently whenever we get beta leaks for new characters, I have to do a lot of manual work in adding the character files, assets, etc.

Objective

Build out some tooling for generating beta files. Ive already done a bit in https://github.com/fribbels/hsr-optimizer/blob/main/misc/betaCharacterGenerator.ts but its still kinda a pain to get through big patches.