R4.12 (user report). The copy holding the instance lock opens a local
door guarded by a random token in its data folder; a second copy sends
its file paths there, lets it take the foreground, and exits 0 instead
of showing "already running". Files join the ely_ui::on_open queue every
app already uses; the main window comes to the front. Also records the
R4.10 round 1 verdict.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
ZacharyZhang-NYandClaude Opus 5.5
5bf2056281