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/AccountMenu.svelte

@@ -44,7 +44,10 @@
 	{@render trigger({ toggle, open })}
 
 	{#if open}
-		<GlassMenu class="absolute top-full right-0 z-(--z-menu) mt-2 overflow-hidden {WIDTH[width]}">
+		<GlassMenu
+			border={false}
+			class="absolute top-full right-0 z-(--z-menu) mt-2 overflow-hidden {WIDTH[width]}"
+		>
 			<MenuItem icon={User} label="Ver perfil" href="/user/{user.sub}" onclick={close} />
 			{@render extraItems?.({ close })}
 			{#if accountUrl}