The functions/<drain name>/index.ts body: the drain shell registers the
handlers for the effects this drain runs and skips the rest, then drains the
written instance. declaredEffectNames is every effect name the registry
exports, so a drain covering all of them passes the registry through.
The
functions/<drain name>/index.tsbody: the drain shell registers the handlers for the effects this drain runs and skips the rest, then drains the written instance.declaredEffectNamesis every effect name the registry exports, so a drain covering all of them passes the registry through.