fix(web): mobile overflow in settings panels

- PanelToolbar: allow wrapping and tighten padding on small screens so the
  primary action (e.g. "创建 API 密钥") no longer runs off the dialog edge.
- ProviderCard header: let the provider name truncate and pin the model-count
  badge and right-side action group with shrink-0 so credits / + controls stay
  inside the card on narrow viewports.

web/src/app/home/components/settings-dialog/panel-layout.tsx

@@ -21,7 +21,7 @@ export function PanelToolbar({
   return (
     <div
       className={cn(
-        'flex shrink-0 items-center justify-between gap-3 border-b px-6 py-3',
+        'flex shrink-0 flex-wrap items-center justify-between gap-2 border-b px-3 py-3 sm:gap-3 sm:px-6',
         className,
       )}
     >