Build - fix(backup): close two teardown gaps flagged in code review Don't SetError("shutdown in progress") from Execute() during teardown. That routes through node-addon-api's parent OnWorkComplete, which constructs OnError(Error::New(env, _error)) inside WrapCallback - still a teardown-time napi touch whose failure mode is ThrowAsJavaScriptException. Return with empty _error instead so dispatch goes through OnOK, where the existing shutting_down_ guard short-circuits before deferred_. Stop reading pro...

Build - fix(backup): close two teardown gaps flagged in code review Don't SetError("shutdown in progress") from Execute() during teardown. That routes through node-addon-api's parent OnWorkComplete, which constructs OnError(Error::New(env, _error)) inside WrapCallback - still a teardown-time napi touch whose failure mode is ThrowAsJavaScriptException. Return with empty _error instead so dispatch goes through OnOK, where the existing shutting_down_ guard short-circuits before deferred_. Stop reading pro... #298