The channel name under 'Voice Connected' was a plain div. Making it navigate
needed more than an onClick: voiceStore never recorded which space the call
was in, and spaceStore.channels only holds the space currently being viewed —
so after navigating away the call's channel was unresolvable, which is also
why the label degraded to a generic 'Voice Channel'.
Capture space and channel name at join time (the only moment they are
reliable) and use them for both the label and the jump. Covers space calls
and DM calls.