If we _weren't_ wrapping in `withTimeout()`, this would be another opportunity for us to crash no misbehaved extensions (e.g. if `initExtension()` returned `{}`).  It's safe as-is now, but we'll have to be careful when touching this code in the future.

Maybe we should put a warning comment over this whole section, noting that _any_ thrown exceptions here will block Brackets from starting up?