Crate twg_observability 

Unified observability surface: metrics, tracing export, and health.

Scaffold only. Three concerns share one HTTP server and read from the same runtime signals (the connector-core backpressure state machine, per-sink circuit breakers, source lag):

• metrics — Prometheus /metrics scrape (disableable via config) plus OTLP push; OTLP defaults to the Zerobus destination, any OTLP endpoint supported.
• tracing — OTEL spans following the record lifecycle, propagated through message headers so a trace crosses the broker.
• health — one health tree, three projections (see health).

Modules

health

The health tree and its three projections.

stats

Live per-stage memory & throughput digest — 30-second rolling window.