Interim handoff. ADR-0028 (query plans / explain) is started:
step 1 (the styled-output-line mechanism, 03d8a09) is done and
committed. handoff-20 carries the full validated build plan
for steps 2-5 with file:line anchors and three implementation
gotchas (the const/static Subgrammar wrinkle, build_show's
positional dispatch, and why steps 2+3 must land as one
commit) so a fresh session implements them without
re-exploring.
claude@clouddev1
c1fcf28e04