1.0 library + player settings: Jellyfin/Link/Files library with details panel, player gear, settings cards, host flag

Library: source switch, selectable cards with a details panel, one merged
Continue row, Latest grouped per series without re-releases, Link page with
previews and recent links, Files embedded. Player: gear popover in both
designs, progress line while controls hide, live hwdec. Settings rebuilt as
cards. State marks the host member (proto stays 9, unreleased); hosting
shows LAN invite addresses; window buttons in fullscreen. fadeThrough keeps
the outgoing view's state.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/desktop/lib/src/jellyfin/home_rows.dart

@@ -0,0 +1,163 @@
+import 'package:sync_relay_core/core.dart';
+
+import 'format.dart';
+
+// What the Jellyfin home rows show, as pure functions over the API lists
+// (tested without widgets).
+
+/// Series not watched for longer than this leave the Continue row, unless
+/// nothing newer is left.
+const continueMaxAge = Duration(days: 60);
+
+/// Added this long after it first aired: a re-release ([isReRelease]).
+const reReleaseAge = Duration(days: 30);
+
+/// One Continue card per series: an episode's series, else the item itself.
+String continueKey(JellyfinItem item) => item.seriesId ?? item.id;
+
+DateTime? _later(DateTime? a, DateTime? b) =>
+    a == null ? b : b == null || !b.isAfter(a) ? a : b;
+
+/// The Continue row: Continue watching ([resume]) and Next up ([nextUp])
+/// merged into one card per series, the series watched most recently first.
+/// A series shows its resume item when that was the last thing played in
+/// it, else its next-up episode. When a series was last played comes from
+/// the resume points and from [recentlyPlayed] (finished episodes, which
+/// next-up items do not carry). Series untouched for [maxAge] are left out
+/// unless nothing else is left; [dismissed] (key -> when) hides a series
+/// until it is played again after that.
+List<JellyfinItem> mergeContinue({
+  required List<JellyfinItem> resume,
+  required List<JellyfinItem> nextUp,
+  List<JellyfinItem> recentlyPlayed = const [],
+  Map<String, DateTime> dismissed = const {},
+  required DateTime now,
+  Duration maxAge = continueMaxAge,
+}) {
+  final finished = <String, DateTime>{};
+  for (final p in recentlyPlayed) {
+    final at = p.userData.lastPlayedDate;
+    if (at != null) finished[continueKey(p)] = _later(finished[continueKey(p)], at)!;
+  }
+  final resumeBy = <String, JellyfinItem>{};
+  final nextBy = <String, JellyfinItem>{};
+  final order = <String>[];
+  for (final r in resume) {
+    final k = continueKey(r);
+    final had = resumeBy[k];
+    if (had == null) order.add(k);
+    final at = r.userData.lastPlayedDate;
+    if (had == null || (at != null && at.isAfter(had.userData.lastPlayedDate ?? DateTime(0)))) {
+      resumeBy[k] = r;
+    }
+  }
+  for (final n in nextUp) {
+    final k = continueKey(n);
+    if (nextBy.containsKey(k)) continue;
+    nextBy[k] = n;
+    if (!resumeBy.containsKey(k)) order.add(k);
+  }
+
+  final cards = <({JellyfinItem item, DateTime? at, int index})>[];
+  for (final (i, k) in order.indexed) {
+    final r = resumeBy[k], n = nextBy[k], done = finished[k];
+    final resumedAt = r?.userData.lastPlayedDate;
+    final JellyfinItem item;
+    if (r != null && (n == null || (resumedAt != null && (done == null || !resumedAt.isBefore(done))))) {
+      item = r;
+    } else {
+      item = n!;
+    }
+    final at = _later(resumedAt, done);
+    final hiddenAt = dismissed[k];
+    if (hiddenAt != null && (at == null || !at.isAfter(hiddenAt))) continue;
+    cards.add((item: item, at: at, index: i));
+  }
+  cards.sort((a, b) {
+    if (a.at == null || b.at == null) {
+      return a.at == b.at ? a.index.compareTo(b.index) : (a.at == null ? 1 : -1);
+    }
+    final c = b.at!.compareTo(a.at!);
+    return c != 0 ? c : a.index.compareTo(b.index);
+  });
+  final fresh = [for (final c in cards) if (c.at != null && now.difference(c.at!) <= maxAge) c.item];
+  return fresh.isNotEmpty ? fresh : [for (final c in cards) c.item];
+}
+
+/// Added to the library long ([age]) after it first aired: a re-upload or
+/// an old season added late, not news. Unknown dates are never re-releases.
+bool isReRelease(JellyfinItem item, {Duration age = reReleaseAge}) {
+  final aired = item.premiereDate, added = item.dateCreated;
+  return aired != null && added != null && added.difference(aired) > age;
+}
+
+/// One card of a "Latest in X" row: [item] is what selecting or putting it
+/// up acts on, [display] gives the picture and title, [subtitle] the line
+/// under it.
+class LatestCard {
+  final JellyfinItem item;
+  final JellyfinItem display;
+  final String subtitle;
+  const LatestCard(this.item, this.display, this.subtitle);
+}
+
+/// A series to show for [episode]: its id, name and poster.
+JellyfinItem seriesOf(JellyfinItem episode) => JellyfinItem(
+      id: episode.seriesId!,
+      name: episode.seriesName ?? episode.name,
+      type: JellyfinItemType.series,
+      isFolder: true,
+      imageTags: {
+        if (episode.seriesPrimaryImageTag != null)
+          JellyfinImageType.primary.apiName: episode.seriesPrimaryImageTag!,
+      },
+      parentBackdropItemId: episode.parentBackdropItemId,
+      parentBackdropImageTags: episode.parentBackdropImageTags,
+    );
+
+/// "Latest in X" from the library's newest items (ungrouped, newest
+/// first): episodes become one card per series (its poster and name,
+/// "S1E1" for a single new episode, else "N new"), in order of the newest
+/// episode; movies and other items stay as they are. With [hideReReleases]
+/// items that [isReRelease] are left out first.
+List<LatestCard> latestCards(List<JellyfinItem> items, {bool hideReReleases = true}) {
+  final kept = hideReReleases ? items.where((i) => !isReRelease(i)) : items;
+  final groups = <String, List<JellyfinItem>>{};
+  final out = <Object>[]; // a JellyfinItem, or a series id (group)
+  for (final i in kept) {
+    final sid = i.seriesId;
+    if (i.kind == JellyfinItemKind.episode && sid != null) {
+      final g = groups[sid];
+      if (g == null) {
+        groups[sid] = [i];
+        out.add(sid);
+      } else {
+        g.add(i);
+      }
+    } else {
+      out.add(i);
+    }
+  }
+  return [
+    for (final o in out)
+      if (o is JellyfinItem)
+        LatestCard(
+          o,
+          o,
+          o.kind == JellyfinItemKind.series && (o.childCount ?? 0) > 1
+              ? '${o.childCount} new'
+              : cardSubtitle(o),
+        )
+      else
+        _seriesCard(groups[o]!),
+  ];
+}
+
+LatestCard _seriesCard(List<JellyfinItem> eps) {
+  final series = seriesOf(eps.first);
+  if (eps.length == 1) {
+    final e = eps.single;
+    return LatestCard(e, series, e.episodeLabel ?? e.name);
+  }
+  return LatestCard(series, series, '${eps.length} new');
+}