Applies the convention from the previous commit across the corpus: gates onto the
latching row, gestures onto the momentary one. 34 files here contain nothing but
`"^NN"` token changes — verified mechanically by normalising every changed line and
checking the -/+ pair is identical once the CC is masked.

## What moved

  52  corpus-wide repairs (tools/fix-button-roles.py, three converging passes)
  29  setlist permutations (tools/migrate-columns.py --apply)

The two tools do different jobs and both are needed. fix-button-roles only MOVES a
control to a free cell, so it declines a case where the target is occupied.
migrate-columns plans a whole column at once, so it can SWAP — which is what the
remaining cases needed: d5's `ply` and d5's take-chooser both wanted a cell, and
exchanging them puts the held flourish on the momentary button while the chooser
(a state: which take plays) takes the latching one. That reading was not designed,
it fell out of role-first assignment with a positional fallback, and it is right.

## Proof it changed no sound

`tools/silent-eval.py --seeded` before and after, twice (after the corpus pass and
again after the permutation): **byte-identical verdicts** both times, including the
same 3 harness build failures (#93). Every button CC seeds to 0 in BootTidal's
`_seed`, so permuting CCs *between two calls in the same block* cannot change
either call's default branch — `midiOn` stays never-applied and `midiOff` stays
always-applied. The edit is event-neutral at boot by construction; the harness run
confirms the construction.

`tools/surface-columns.py` still reports 83/83 orbits column-aligned with 0
renumbers needed — the swaps stay inside each orbit's own column, so the property
phase 2 established is preserved.

## Still open, deliberately

12 sites where ONE orbit drives two gestures. Only one momentary cell exists per
column, so the second has to sit on the latching row. Reported as PV010 `info` and
not repaired: the real fix is gSel (#54), folding a pair of gestures onto one
control. Naming it beats hiding it.