remove `trace_id` entirely, use meta-maps in more places#39

c-cube wants to merge 2 commits intomainc-cube/ocaml-trace:mainfrom

simon/no-more-trace-id-in-explicit-spans-2025-12-12c-cube/ocaml-trace:simon/no-more-trace-id-in-explicit-spans-2025-12-12Copy head branch name to clipboard