fix: mobile layout and touch target improvements for admin settings

- SettingsTableRow: stack name above controls on mobile, show action
  buttons without hover (max-lg:opacity-100)
- SettingsMobileTabs: increase touch targets to 44px, add scroll spacers
- QuickToggles: increase chip touch targets
- SettingInput: increase display button touch target
- AdminSettings: add bottom padding buffer to mobile layout

src/components/admin/QuickToggles.tsx

@@ -39,7 +39,7 @@ export function QuickToggles({ settings, onUpdate, disabled, className }: QuickT
               onClick={() => onUpdate(setting.key, isOn ? 'false' : 'true')}
               disabled={disabled}
               className={cn(
-                'flex items-center gap-2 rounded-lg border px-2.5 py-1.5 text-xs font-medium transition-all',
+                'flex items-center gap-2 rounded-lg border px-2.5 py-2.5 text-xs font-medium transition-all',
                 isOn
                   ? 'border-success-500/20 bg-success-500/[0.08] text-dark-100'
                   : 'border-dark-600/50 bg-dark-700/20 text-dark-400',