feat(call-to-play)!: coordinate game sessions across peers

Implement the launcher design as a production peer-to-peer feature. Call to
Play actions are immutable, validated events broadcast over the existing QUIC
control channel, deduplicated in a bounded in-memory history, and exchanged in
Hello/HelloAck so late joiners reconstruct current calls.

Add the Tauri bridge and modular launcher surfaces for play-now and scheduled
calls, check-in, readiness buffers, role-aware controls, chat, tickers, and
actual caller launch. A deterministic frontend reducer derives presentation
state from replicated history. Extend the JSONL peer harness with publish/list
commands and a three-peer live-delivery and late-join scenario.

This intentionally raises the only supported wire protocol from version 5 to
version 6; older builds are not supported. Document the transport architecture
and exclude generated peer-test state from Docker build contexts.

Test Plan:
- `just fmt` -- passed
- `just clippy` -- passed
- `just test` -- passed
- `just frontend-test` -- passed, 20 tests
- `just build` -- passed
- `just peer-cli-tests S2 S48` -- passed
- `git diff --cached --check` -- passed

crates/lanspread-tauri-deno-ts/src/windows/MainWindow.tsx

@@ -10,12 +10,15 @@ import { ConfirmRemoveDownloadModal } from '../components/modals/ConfirmRemoveDo
 import { SettingsDialog } from '../components/modals/SettingsDialog';
 import { NoDirectoryState } from '../components/empty/NoDirectoryState';
 import { EmptyResultsState } from '../components/empty/EmptyResultsState';
+import { CallToPlayTicker } from '../components/calltoplay/CallToPlayTicker';
+import { CallToPlayOverlay } from '../components/calltoplay/CallToPlayOverlay';
 
 import { useGameDirectory } from '../hooks/useGameDirectory';
 import { useGames } from '../hooks/useGames';
 import { useGameActions } from '../hooks/useGameActions';
 import { useThumbnails } from '../hooks/useThumbnails';
 import { useSettings } from '../hooks/useSettings';
+import { useCallToPlay } from '../hooks/useCallToPlay';
 
 import { Game } from '../lib/types';
 import { applyFilterAndSort, countByFilter, needsUpdate } from '../lib/gameState';
@@ -72,10 +75,13 @@ export const MainWindow = () => {
     const games = useGames(rescan);
     const actions = useGameActions(games, settings);
     const thumbnails = useThumbnails();
+    const callToPlay = useCallToPlay(settings.username);
 
     const [openGameId, setOpenGameId] = useState<string | null>(null);
     const [removeGameId, setRemoveGameId] = useState<string | null>(null);
     const [settingsOpen, setSettingsOpen] = useState(false);
+    const [callToPlayOpen, setCallToPlayOpen] = useState(false);
+    const [focusedCallId, setFocusedCallId] = useState<string | null>(null);
     const visibleGames = useMemo(
         () => hasGameDirectory ? games.games : [],
         [games.games, hasGameDirectory],
@@ -154,8 +160,22 @@ export const MainWindow = () => {
                 sort={settings.sort}
                 setSort={(v) => setSetting('sort', v)}
                 kebabItems={kebabItems}
+                nominations={callToPlay.nominations}
+                onOpenCallToPlay={() => {
+                    setFocusedCallId(null);
+                    setCallToPlayOpen(true);
+                }}
             />
             <main className="grid-wrap">
+                <CallToPlayTicker
+                    nominations={callToPlay.nominations}
+                    games={games.games}
+                    accent={settings.accent}
+                    onOpen={(callId) => {
+                        setFocusedCallId(callId);
+                        setCallToPlayOpen(true);
+                    }}
+                />
                 {hasGameDirectory ? (
                     <>
                         <ResultsBar shown={filteredGames.length} total={counts.all} />
@@ -220,6 +240,25 @@ export const MainWindow = () => {
                     onClose={() => setSettingsOpen(false)}
                 />
             )}
+
+            {callToPlayOpen && (
+                <CallToPlayOverlay
+                    nominations={callToPlay.nominations}
+                    games={games.games}
+                    username={callToPlay.username}
+                    actions={callToPlay.actions}
+                    focusId={focusedCallId}
+                    transportReady={callToPlay.transportReady}
+                    error={callToPlay.error}
+                    getThumbnail={thumbnails.get}
+                    totalPeerCount={games.totalPeerCount}
+                    onLaunch={handlePrimary}
+                    onClose={() => {
+                        setCallToPlayOpen(false);
+                        setFocusedCallId(null);
+                    }}
+                />
+            )}
         </div>
     );
 };