EZO Watcher telemetry collector

POST /v1/events receives anonymous usage events from the ezo-watcher CLI and server.
What is sent, what never is, and how to turn it off: https://github.com/ezolabs/ezo-watcher/blob/main/docs/telemetry.md
This Worker's source: https://github.com/ezolabs/ezo-watcher/tree/main/deploy/telemetry
Opt out: `watcher telemetry disable`, or set DO_NOT_TRACK=1.