Logger.error() called this._log('error',...) but dropped the return value.
_log returns the writeErrorLog(...) promise for error level, so every
await logError(...)/await log.error(...) caller was awaiting undefined —
the error.log disk write was fire-and-forget. This caused:
1. __tests__/logging.test.js 'captures request context' to flake in the
full suite (test read error.log before the un-awaited appendFile
completed; passed in isolation).
2. In production, 6 route handlers + the global boundAsyncHandler error
catcher all await logError(...) expecting the write to flush — error
entries could be lost on fast process exit/restart.
Fix: add 'return' so the promise propagates. Verified: logging test
passes 10/10 full-suite runs (was ~1/6 failure rate). No behavior change
for debug/info/warn (they never wrote to disk).
Hermes
1c8f55edc1