v0.84.2

Fixed

• A query issued deep inside wpdb is labelled again. SHOW FULL COLUMNS reaches the query filter through four transport frames — update(), process_fields(), get_table_charset(), get_results() — and ORIGIN_DEPTH (8) was sized for a hook, whose origin is the fifth frame. Climbing past that many frames ran the walk out of stack, so origin_frame() returned '' and the span carried no label at all. The climb now walks TRANSPORT_ORIGIN_DEPTH (16); the hook path keeps its 8 frames and its measured 0.9us, and the deeper walk is already gated on trace_callers being 0.