Function otel_span_attribute_mapping 

pub fn otel_span_attribute_mapping() -> &'static [(&'static str, &'static str, Option<&'static str>)]

The single compiler-owned bridge from the closed noxid.trace.v1 record schema to OpenTelemetry semantic-convention attributes. Keeping duplicate source fields (such as code) explicit makes the exported contract golden- testable without teaching the JavaScript runtime Noxid semantics.