fix(ui): center skills empty state and fix terminal toolbar overlap (#1064)

* fix(ui): center skills empty state and fix terminal toolbar overlap

Fix two UI layout issues in the settings and terminal views.

Skills empty state:

- Add h-full to the max-w-3xl content wrapper so flex centering works

- Make book icon responsive (h-10 w-10 sm:h-12 sm:w-12)

- Add px-4 padding for narrow viewports

Terminal toolbar:

- Reserve right padding (pr-20) for dock fullscreen/close buttons

- Remove pb-1 from quick keys to fix vertical misalignment

- Change shrink-0 to min-w-0 for graceful shrinking on narrow widths

* ref(ui): gate pr-20 padding on desktop runtime only

packages/ui/src/components/views/SettingsView.tsx

@@ -670,7 +670,7 @@ export const SettingsView: React.FC<SettingsViewProps> = ({ onClose, forceMobile
             <ErrorBoundary>{renderPageSidebar(settingsSlug, {})}</ErrorBoundary>
           </div>
           <div className="flex-1 overflow-auto scrollbar-none bg-background">
-            <div className="mx-auto w-full max-w-3xl">
+            <div className="mx-auto h-full w-full max-w-3xl">
               <ErrorBoundary>{renderPageContent(settingsSlug)}</ErrorBoundary>
             </div>
           </div>
@@ -680,7 +680,7 @@ export const SettingsView: React.FC<SettingsViewProps> = ({ onClose, forceMobile
 
     return (
       <div className="h-full overflow-auto scrollbar-none bg-background">
-        <div className="mx-auto w-full max-w-3xl">
+        <div className="mx-auto h-full w-full max-w-3xl">
           <ErrorBoundary>{renderPageContent(settingsSlug)}</ErrorBoundary>
         </div>
       </div>