* fix(studio): keep an edit's preview waiting while the window draws no frames
An edit that reloads the preview loads it hidden and swaps it in once it
has drawn two frames. Its 45 s wait ran on the wall clock and paused only
when the page reported itself hidden, but a window behind others on some
Linux desktops draws no frames while still reporting visible. The swap
then gave up and the old preview stayed on screen until the next edit.
A wait budget in which no frame was drawn is no longer spent; the next
frame restarts the full budget, as showing a hidden tab already does.
* fix(studio): keep the frame-wait note in the budget comment