Mint a first-party localStorage anonId, thread it onto play/share beacons,
persist it via EventController, and add all-time distinct-listener counts
(site/track/release). Storage columns + indexes already existed from 16.1.
Proxy chains any inbound XFF with the connection IP before relaying upstream; UseForwardedHeaders resolves it to the limiter's partition key. Documents the EventRepository first-play counter race (unique index is the backstop).