pub fn init(dev_mode: bool, otel_endpoint: Option<&str>)Expand description
Initialize the global tracing subscriber.
In dev mode: pretty-printed stdout.
In production: JSON + optional OTLP exporter (gRPC/tonic to otel_endpoint).
If otel_endpoint is Some, a batch OTLP trace exporter is installed and
spans are exported to the given gRPC endpoint (e.g. http://localhost:4317).
An OTLP metrics pipeline is also installed when an endpoint is provided.