Multi-core support and better legendary selection UI

[kopikocoffee]

Hi! I made a small fork of Brainstorm and wanted to share a few improvements I ended up really liking:

1. Multi-core support for the reroller, so it can use multiple CPU cores more effectively.
2. A cleaner Legendary Joker selection UI, with direct card-based picking instead of cycling through options.
3. Support for mod Jokers as well, so the legendary pool stays in sync with modded content.
4. Added Temperance search support for the first tarot draw / charm pack reroll logic.

I’ve been using it locally and it feels a lot nicer in practice. If you’re interested, I’d be happy to open a PR or adapt the changes to match your preferred style.

Fork: https://github.com/kopikocoffee/Brainstorm