Per-event preferences

Notification settings are a matrix rather than a switch. Twelve event types, each of which can go to email, to Slack, or to neither, set per person rather than once for the account.

They are grouped into four kinds, and the grouping is the useful part. Experiment lifecycle covers started, ended and deployed. Results covers a significant positive and a significant negative. Health covers a split mismatch, no data, overdue, and a blocked automation. Account covers an implementation marked done, a user invited and a website created.

Health is deliberately kept separate from lifecycle rather than merged into one experiments group. Those rows say an experiment cannot be trusted, which is a different decision to make than "tell me when things start", and burying them together is how somebody switches off the alarm along with the noise.

The catalogue only contains types something actually emits. An entry with no producer reads as a feature that exists and silently never fires, which is worse than not offering it.