The 0.5s ScheduleRepeatingTimer poll that caught these frames couldn't
catch them before their first-ever :Show() this session, since they're
created on-demand the instant the player opens them -- native art got
one frame of paint before the poll's next tick could skin it.
Switched to a generic ADDON_LOADED listener instead: it fires
synchronously (before control returns to whatever opens the frame)
the moment the owning addon finishes loading, so skinning now lands
before the frame is ever shown. Confirmed in-game via an ADDON_LOADED
probe on the talent frame's addon before implementing.
Also fixes a regression this introduced: TalentFrame's CropBackground
was caching the background texture's "original" tex coords on its
first-ever call for later crop math. That first call now happens
pre-Show, before Blizzard's own code sets the texture's real art-tile
region, so it was permanently baking in the XML-template default
(full 0..1) as the baseline. Moved the crop to run only from OnShow,
where the real coords are already set.
Skins the outer window, close button, search box, Filter dropdown
(and its arrow and popup panel), Purchase/Deliver buttons, and the
grid pager arrows. Removes nothing else -- the portrait originally
suspected at the top-left corner turned out not to exist as a
separate element, and the card grid/preview panel are left native.