LyftData application log router tutorial fixtures

All records are synthetic. Schema: lyftdata-tutorial-application-log-router-v1.
Gateway records use source/severity/message. Worker records use
component/level/text so the workflow must normalize two shapes.

Verify after download:
  sha256sum gateway.jsonl worker.jsonl expected-summary.json

On macOS use:
  shasum -a 256 gateway.jsonl worker.jsonl expected-summary.json