fix(arch): comprehensive architecture audit fixes (#44)

fix: comprehensive frontend-backend integration fixes

fix(ci): format code and add ErrorBoundary tests to pass CI

fix(frontend): refactor retry logic to use loop instead of recursion

fix(frontend): add cold start retry with waking_up state (BUG-001)

feat(api): async job queue with comprehensive test coverage (#36)

feat(frontend): React + Vite + NiiVue frontend (replaces Gradio) (#32)