The cached config (LS_CFG) painted its first frames with _zoom=1 because
the saved per-space zoom was applied only by _restoreZoom()'s rAF after
the server config round-trip - the plan visibly jumped to the saved scale.
- setConfig now arms _zoom from LS_ZOOM for the resolved space before the
first view computation (view mode, no established view only);
- _restoreZoom applies the view synchronously when the stage is already
measured (space tabs, kiosk carousel, editor exit included); the rAF
path remains only for an unmeasured stage, where updated() already fits
with the correct zoom before the first paint.
New smoke_zoom_flash.mjs samples every rAF frame from the first possible
moment with a primed config cache, saved zoom 1.8 and a 350 ms server
delay: a visible stage with a default-scale viewBox fails the run
(22 such frames before the fix, 0 after).
