fix: usable layout when the window is small (#981)

* fix(layout): collapse browse toolbar to icons on compact width

On a narrow window the labelled filter buttons wrapped into several rows
and, being a fixed-height sticky header, starved the album grid below them
down to a clipped strip. Wrap each toolbar label in a hideable span and drop
to icon-only in compact (mobile) mode; icons keep their tooltip and
aria-label so the action stays discoverable.

* fix(window): raise minimum window size to 520x640

The old 360x480 floor let the window shrink far past the point the layout
holds together. Floor it at a laptop-friendly size where the compact layout
(icon toolbar + scrollable lists) still works.

* fix(player): scale mobile cover to fit short windows

The cover width was viewport-derived with no height bound, so on a short
window the square grew past its slot and overlapped the title. Bind it to
the shrinkable wrap via max-height and keep it square with auto sizing.

* docs: changelog for small-window layout fixes (#981)

src/components/SortDropdown.tsx

@@ -98,7 +98,7 @@ export default function SortDropdown<V extends string>({ value, options, onChang
         style={{ display: 'flex', alignItems: 'center', gap: '0.4rem' }}
       >
         <ArrowDownUp size={14} />
-        {current?.label ?? value}
+        <span className="toolbar-btn-label">{current?.label ?? value}</span>
       </button>
 
       {open && createPortal(