Interface CacheDiagnosticsSnapshot

One cache source's snapshot (M98i): the counters its owned CacheService observed.

coverage is always owned-instance: the source describes the CacheService its own plugin created, never whatever is currently registered under the cache token, never direct store calls, and never a replacement service. alias is null exactly when the plugin was not opted into observation (state: 'disabled'). dropped counts observations for which no record slot was available (saturating). A collection failure clears records and reports collection-failed.