docs(launcher): add Call to Play specification and design reference

Extend the launcher design specification and prototype reference with the
"Call to Play" multiplayer coordination feature and clean up top-bar chrome.

Key additions and changes:
- Spec & Roadmap: Document Call to Play mechanics in SPEC.md, including Play
  Now / Scheduled call flavors, 15-minute check-in windows, top-bar button
  with active count badge, quick-bar ticker stack above grid, overlay modal,
  and per-call group chat. Update design/README.md.
- Components & Logic: Add calltoplay.jsx and ctp-chat.jsx components for call
  creation, status progression, and chat. Extend data.jsx with a mock peer
  roster (PEERS) and helper functions for peer install count tracking.
- Top-bar Cleanup: Move game-folder configuration from top bar into Settings ->
  Library, freeing top-bar space for the Call to Play action button.
- Styling & Layout: Add CTP quick-bar, ticker, badge, card, and chat styles to
  styles.css, and integrate CTP components into launcher.jsx, components.jsx,
  and SoftLAN Launcher.html.

Test Plan:
- `git diff --cached --check` -- passed (no trailing whitespace or conflict markers)
- `cargo check --workspace` -- passed cleanly
- Manual review of staged diff across 9 design/launcher files -- confirmed clean staging

design/launcher/design_reference/launcher.jsx

@@ -15,6 +15,8 @@ function applyFilterAndSort(games, filter, sort, query) {
   } else if (sort === 'recent') {
     const order = { installed: 0, local: 1, none: 2 };
     g = [...g].sort((a, b) => order[a.state] - order[b.state] || b.version.localeCompare(a.version));
+  } else if (sort === 'peers') {
+    g = [...g].sort((a, b) => installedPeersFor(b).length - installedPeersFor(a).length || a.title.localeCompare(b.title));
   }
   return g;
 }
@@ -25,6 +27,8 @@ function Launcher({
   initialFilter = 'all', initialSort = 'recent', initialQuery = '',
   initialOpenGame = null,
   initialSettingsOpen = false,
+  seedCallToPlay = [],
+  initialCtpOpen = false,
 }) {
   const { density, aspect, accent, bg } = tweaks;
   const [filter, setFilter] = useState(initialFilter);
@@ -32,6 +36,11 @@ function Launcher({
   const [query, setQuery] = useState(initialQuery);
   const [openGame, setOpenGame] = useState(initialOpenGame);
   const [settingsOpen, setSettingsOpen] = useState(initialSettingsOpen);
+  const [ctpOpen, setCtpOpen] = useState(initialCtpOpen);
+  const [ctpFocusId, setCtpFocusId] = useState(null);
+
+  const nomUsername = tweaks.username && tweaks.username.trim() ? tweaks.username.trim() : 'you';
+  const ctp = useNominations({ username: nomUsername, seed: seedCallToPlay });
 
   const counts = useMemo(() => countByFilter(GAMES), []);
   const list = useMemo(() => applyFilterAndSort(GAMES, filter, sort, query), [filter, sort, query]);
@@ -66,6 +75,7 @@ function Launcher({
               <SortMenu value={sort} onChange={setSort} accent={accent}/>
             </div>
             <div className="topbar-right-trail">
+              <CallToPlayButton nominations={ctp.nominations} onClick={() => setCtpOpen(true)}/>
               <KebabMenu items={menuItems}/>
             </div>
           </div>
@@ -79,6 +89,7 @@ function Launcher({
             </div>
             <div className="topbar-row1-right">
               <StorageMeter accent={accent}/>
+              <CallToPlayButton nominations={ctp.nominations} onClick={() => setCtpOpen(true)}/>
               <KebabMenu items={menuItems}/>
             </div>
           </div>
@@ -93,6 +104,8 @@ function Launcher({
       )}
 
       <main className="grid-wrap">
+        <CallToPlayTicker nominations={ctp.nominations} accent={accent}
+                          onOpen={(id) => { setCtpFocusId(id); setCtpOpen(true); }}/>
         {variant === 'single' && (
           <div className="results-bar">
             <div className="results-count">
@@ -113,6 +126,12 @@ function Launcher({
       {settingsOpen && setTweak && (
         <SettingsDialog settings={tweaks} onChange={setTweak} onClose={() => setSettingsOpen(false)}/>
       )}
+      {ctpOpen && (
+        <CallToPlayOverlay nominations={ctp.nominations} username={nomUsername} accent={accent}
+                           focusId={ctpFocusId}
+                           onClose={() => { setCtpOpen(false); setCtpFocusId(null); }}
+                           actions={{ createNomination: ctp.createNomination, respond: ctp.respond, rsvp: ctp.rsvp, sendMessage: ctp.sendMessage, leave: ctp.leave, cancel: ctp.cancel, startNow: ctp.startNow, addTime: ctp.addTime }}/>
+      )}
     </div>
   );
 }