Type Alias: QualityLevel

type QualityLevel = "excellent" | "good" | "poor" | "critical" | "unknown";

A connection's quality grade, as the server grades it, in the client.

The server derives quality once, from ReportStats, so that all three SDKs agree on what "poor" means — and this is the same ladder, applied to the same samples, so what the user sees and what support sees are one measurement rather than two that disagree by a grade.

It runs locally as well as on the server because it has to: a client whose uplink has just died cannot be told by the server how bad its uplink is, and that is precisely when the recovery ladder needs to start.