CI / check (push) Failing after 7m34s
k.go('arcade') schedules the scene callback on frameEnd, not synchronously.
start() was called before fighters existed, causing "Cannot read properties
of undefined (reading 'obj')". Fix: await a readiness promise that resolves
once the scene callback has created the fighters.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>