The desktop toolbar carried two identical "minus 1 plus" instance steppers side
by side, one after Run and one after Run Shell. The second (#shellCount) is
gone for a cleaner strip.
Run Shell keeps the capability: both launch paths now read the remaining
#tabCount control through _toolbarInstanceCount(), which also makes an absent
stepper read as 1 instead of throwing. That matters because the group is
display:none on phones and tablets, and because the Run dropdown's
Terminal / Shell entry routes through runShell() too, where the visible counter
was previously ignored.
Desktop only: both steppers were already hidden under 1024px.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>