index/index.js:1041:Wt calls index(sub.root, { home, track, _seen }), dropping
opts.links, opts.kv, opts.subs and opts.fork, so a caller asking for
the commit half alone still gets the full LINK/SYM/TRI scan plus a kv sweep in
every submodule, and a --fork n never reaches them. Found in the 2026-09-18
index review.
Forward the opts object with _seen overridden.
_seen overridden: a two-field
copy is what dropped links, kv, subs and fork, and any
knob added later would be dropped the same way.tip is the ONE field left behind — it names a commit of the
parent, and no history of the sub's holds it.