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/de/settings.ts

@@ -324,6 +324,7 @@ export const settings = {
   tabThemes: 'Themes',
   themesYourThemesTitle: 'Deine Themes',
   themesCvdTooltip: 'Farbfehlsichtigkeits-sicher – Deuteranopie, Protanopie, Tritanopie',
+  themeAnimationWarning: 'Dieses Theme nutzt Animationen, die auf deinem Setup (Nvidia/Linux oder Compositing aus) die CPU-Last erhöhen können.',
   themeStoreTitle: 'Theme-Store',
   themeStoreSubmitText: 'Eigenes Theme gebaut? Teil es mit der Community — mehr Infos im Themes-Repository.',
   themeStoreSubmitLink: 'Themes-Repository öffnen',