jellyfin panel app: browse, detail and player

adds the /jellyfin screen and its two panels (nav + view) on top of the
jellyfin sidecar, following the photos/invoiceshelf shape.

the transcode path is a progressive mp4 rather than hls, so no hls.js
dependency is added under the frozen-install rule. that stream has no
length and no byte ranges, so the player owns its own scrubber and seeks
by re-negotiating at a new startTimeTicks, tracking offset + currentTime;
a direct file keeps native controls. the hls url is still returned, so
switching later is a player change only.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/apps/officer-web/Screens/Dashboard/index.tsx

@@ -16,6 +16,7 @@ export * from './Music';
 export * from './Soulseek';
 export * from './Headscale';
 export * from './Photos';
+export * from './Jellyfin';
 export * from './Transmission';
 export * from './Invoices';
 export * from './Wallet';