Shrink menu item text and drop the border on the account dropdown

MenuItem used text-sm (14px) for its label, which read as oversized
for a dropdown; drop to text-xs (12px). This is a shared component
(AccountMenu, ContextMenu, MobileHeader's menu), so all of them get
the more compact sizing.

Add a border prop to GlassMenu (default true, unchanged for
ContextMenu) and set it false specifically on AccountMenu's dropdown,
per feedback that its border didn't fit.

web-player/src/lib/components/ui/overlay/GlassMenu.svelte

@@ -4,12 +4,16 @@
 	interface Props {
 		class?: string;
 		style?: string;
+		border?: boolean;
 		children: Snippet;
 	}
 
-	let { class: klass = '', style = '', children }: Props = $props();
+	let { class: klass = '', style = '', border = true, children }: Props = $props();
 </script>
 
-<div class="glass-panel animate-pop rounded-panel border border-hairline p-1.5 {klass}" {style}>
+<div
+	class="glass-panel animate-pop rounded-panel p-1.5 {border ? 'border border-hairline' : ''} {klass}"
+	{style}
+>
 	{@render children()}
 </div>