Battle caster

[x] - basic map casting to second tab [x] - scaling maps [ ] - remember map scale for previously open maps [ ] - fog of war [x] - basic soundboard [ ] - load folder with sounds [ ] - bind sounds to keys [ ] - rework file manager to support auth [ ] - split app to public cloud hosted part and local file hosting [ ] - support local filesystem api [ ] - wled sound effect sync? [ ] - caster mini app to sync multiple chromecast to single tab.