feat(themes): warn about animated themes on high-CPU setups (#1020)

* feat(themes): warn about animated themes on high-CPU setups

Show a warning icon + tooltip on animated themes (those defining
@keyframes) in the store and in Your Themes, on Linux setups where
animation is costly — the Nvidia WebKit quirk is active or compositing
is forced off. The Nvidia detection already runs once at startup; its
result is recorded (theme_animation.rs) and read via a new
theme_animation_risk command — no GPU re-probe. Display-only; never
shown off Linux. The animated flag comes from the registry (store) or
the theme CSS (Your Themes).

* docs(themes): note the animated-theme warning PR in the Theme Store entry

src/locales/nb/settings.ts

@@ -323,6 +323,7 @@ export const settings = {
   tabThemes: 'Temaer',
   themesYourThemesTitle: 'Dine temaer',
   themesCvdTooltip: 'Fargeblind-sikker – deuteranopi, protanopi, tritanopi',
+  themeAnimationWarning: 'Dette temaet bruker animasjoner som kan øke CPU-bruken på oppsettet ditt (Nvidia/Linux eller compositing av).',
   themeStoreTitle: 'Temabutikk',
   themeStoreSubmitText: 'Laget ditt eget tema? Del det med fellesskapet — mer info i tema-repoet.',
   themeStoreSubmitLink: 'Åpne tema-repoet',