Brings the v3 control surface work onto master, as PLN called it: "this is the
new tooling/state". The arc is one idea repeated — the driver owns the truths
the hardware refuses to keep.

- it plays: four defects between the driver and a live SuperCollider, all of
  them identity bugs (a port's NAME is not the port)
- it speaks a language: role hue x value lightness, the DJF's diverging
  blue -> breathing-green-zero -> red, glowing at the track's tempo
- it holds state the v3 board dropped: offset-64 relative values, row-E
  latches, paint reasserted every two seconds
- it says what each control DOES, in PLN's own words parsed from his .tidal
  ("Le Delay rose!!!", "HANDS IN THE AIR"), across all 34 display targets
- it follows the track: the editor already published it, the driver only had
  to read — remap, relabel, repaint and reset the lap clock on a change, and
  re-read on save so mapping a control lights the board within a second
- the tempo can be a knob, with landmark detents replacing the notch the v3
  encoders lack, and a bar countdown for the mute-drop transition
- and the rig around it: Ardour hears the surface again, RIG UP owns the
  ordering SuperDirt needs, midiviz replaced the transcript with a picture

Also aboard: a display-semantics probe that asks the device instead of us
guessing, realtime.tidal for composing without the crossfade, and the corpus
marked for quantise at all 14 tempo-knob sites.

Backward compatibility is the standing constraint and it holds: the corpus
speaks v2 forever, everything v3 lives in the driver, and a classic Launch
Control XL still works with nothing running.