pub fn init_observability(config: &Config)Expand description
Install the global tracing subscriber: an RUST_LOG-driven fmt layer plus,
when the otlp feature is built and an OTLP endpoint is configured
(ADR-0059), an OpenTelemetry traces export layer. Safe to call once at
startup; a second call is a no-op. A failure to build the OTLP exporter logs a
warning and falls back to fmt-only rather than taking the server down.