The rewire (tray Launch Gig -> POST /api/rig, arm-then-confirm) is
written and loads clean, but testing it end-to-end killed Ardour:
launchers.launch('ardour') reported 'launched' while Ardour was already
running, a second instance collided with the first over the session
lock, and both exited -- taking all 12 orbit links with them.

A false negative in is_running() wired to a tray button is worse than
the mislabeled button it replaces, so it does not ship until launch()
fails closed. Parked as a patch beside the note rather than committed
(unvalidated) or left loose in the worktree (this checkout is shared and
another session commits into it by pathspec).

Carries the rest of the session's open ends too: the perf.sh redeploy
that is committed but not live, gig-up's four pre-existing NO-GO
blockers, perf-tray's 2.6GB RSS, and why gig-down is blocked on the
Freebox being down.