Add:iOS support offline episode chapters #675

ios/App/Shared/models/local/LocalLibraryItem.swift

@@ -177,6 +177,7 @@ extension LocalLibraryItem {
             audioTracks.append(AudioTrack.detachCopy(of: track)!)
             duration = track.duration
             displayTitle = episode.title
+            episode.chapters.forEach { chapter in chapters.append(Chapter.detachCopy(of: chapter)!) }
         } else if let tracks = self.media?.tracks {
             tracks.forEach { t in audioTracks.append(AudioTrack.detachCopy(of: t)!) }
         }

ios/App/Shared/models/local/LocalPodcastEpisode.swift

@@ -18,6 +18,7 @@ class LocalPodcastEpisode: Object, Codable {
     @Persisted var desc: String?
     @Persisted var audioFile: AudioFile?
     @Persisted var audioTrack: AudioTrack?
+    @Persisted var chapters = List<Chapter>()
     @Persisted var duration: Double = 0
     @Persisted var size: Int = 0
     @Persisted(indexed: true) var serverEpisodeId: String?