fix(downloads): call a request a request, and mark it with a bookmark

The feature was renamed to requests and the copy was not. The badge on
every Explore card and track row still offered "Want track X", the
album page's button read "Want this" / "Wanted", the artist page's
release menu said "Want This", and the Downloads empty state told the
user to look for a control by a name nothing rendered.

The `queued` badge is a bookmark rather than an hourglass. An hourglass
says "wait, this is under way", which overstates what a request is:
nothing may be downloading, nothing may ever be found, and the list is
somewhere a user can leave one indefinitely. A bookmark says the honest
thing -- it is on your list -- and reads as the opposite of the plus
that put it there, which is what a toggle's two states have to do.

The backend's `'wanted'` request state is deliberately untouched: it is
a stored enum, not copy.

Also removes a dead duplicate branch in the badge's `render()`. The
first `if (this.actionable)` returned before the ring was built, so a
partly-held album that could still be requested drew a plus instead of
its progress arc.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MeQt5hgXg5YGoNZQ9ozG7L

frontend/test/components/chrome.test.ts

@@ -166,7 +166,7 @@ describe('<library-status-indicator>', () => {
       glyphs.push(shadow(el, 'wa-icon')?.getAttribute('name'));
     }
 
-    expect(glyphs).toEqual(['check', 'hourglass-half', 'plus']);
+    expect(glyphs).toEqual(['check', 'bookmark', 'plus']);
   });
 
   it('phrases its label around the entity it describes', async () => {