Telemetry

Use Logger (os) with a subsystem and category, read via Console or log stream --predicate. Docs: https://developer.apple.com/documentation/os/logger.

• No print as telemetry. Never log secrets, tokens, personal data, or document contents.
• Signposts only for timing spans.
• Do not claim an event is wired until you saw it in log stream or captured output. Remove logs that are not useful afterward.