- pure rollup accumulators with tests; daily upserts keyed date/metric/dim
- alert checks with db-backed cooldown and push to admin players
- in-process scheduler started from health probes
- health endpoint checks pb + supertokens, stale-while-revalidate, always 200
- sse connection counter moved to emitter
- telemetry feature server fns: events/errors/groups/rollups/alerts/status
