Function record_invocation 

pub fn record_invocation(
    plugin: &PluginId,
    qname: &QName,
    kind: InvocationKind,
    rows: u64,
    elapsed: Duration,
    ok: bool,
)

Tracing helper: emit a single structured event for one plugin call.

Real M11 cutover wraps each invocation in a tracing::info_span! using these field names; pre-cutover, this function emits a debug event so the wiring is exercised end-to-end through the existing tracing subscriber.