Two commits, 4 files, reviewed as a diff against master.

  tempo_timeline.py       tempo per window in a rendered track, to test whether
                          a planned track was actually played. Answered WAP: not
                          played (median 124.5 over segment 1, nothing at 133
                          above the confidence floor), calibrated first on a
                          declared-160 track which returned 161.5.
  gigmeta sidecar         PLN's confirmed set time (~20:30), his verbatim
                          approval of "Le Jardin", and the WAP question moved
                          from open to resolved with both sources named.
  build_gig_tracksjson    resolve the frontmatter-only fields before writing
                          _provenance, so their origin is recorded whether or
                          not --md-out was passed.
  TASKS_DUMP.md           the board after the release session: six resume
                          points, two of which are the kind that look done when
                          they are not.

Two bugs of mine are in the branch rather than tidied out of it: the octave fold
was an infinite loop for any value a sub-octave band cannot represent, and the
per-frame FFT loop was ~100k Python-level calls for a five-minute stem.