Add chapters, history, bookmarks, live download progress, and i18n

- Chapter navigation with auto-scroll to current chapter and end-of-chapter sleep timer
- Opt-in listening history (local-only) with XML export and per-item quick menu
- Bookmarks with server sync via Audiobookshelf API
- Live MB counter during downloads via URLSessionDownloadTask delegate
- In-progress downloads shown in "Heruntergeladen" with dimmed cover + ring overlay
- Cover image cache (50 MB memory / 500 MB disk URLCache)
- German/English localization (de.lproj, en.lproj)
- Loading spinner now triggers immediately on view switch instead of waiting for the network

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ABS Client/Audiobookshelf swift/Views/PlayerBar.swift

@@ -3,8 +3,11 @@ import SwiftUI
 struct PlayerBar: View {
     @Environment(AppState.self) private var app
     @AppStorage("skipDurationSeconds") private var skipSeconds: Int = 30
+    @AppStorage("historyEnabled") private var historyEnabled: Bool = false
     @State private var scrubbing: Bool = false
     @State private var scrubValue: Double = 0
+    @State private var showDetails: Bool = false
+    @State private var showFullHistory: Bool = false
 
     var body: some View {
         if let item = app.currentItem {
@@ -21,6 +24,14 @@ struct PlayerBar: View {
                     .background(.bar)
             }
             .transition(.move(edge: .bottom).combined(with: .opacity))
+            .sheet(isPresented: $showDetails) {
+                PlaybackDetailsView()
+                    .environment(app)
+            }
+            .sheet(isPresented: $showFullHistory) {
+                FullHistoryView()
+                    .environment(app)
+            }
         } else if app.isPreparingPlayback {
             VStack(spacing: 0) {
                 Divider()
@@ -77,6 +88,17 @@ struct PlayerBar: View {
 
                 Spacer()
 
+                if historyEnabled {
+                    historyQuickMenu
+                }
+
+                Button { showDetails = true } label: {
+                    Image(systemName: "list.bullet.indent")
+                        .font(.system(size: 22))
+                }
+                .buttonStyle(.plain)
+                .disabled(!app.player.isReady)
+
                 sleepMenu
 
                 rateMenu
@@ -119,6 +141,17 @@ struct PlayerBar: View {
 
             Spacer(minLength: 0)
 
+            if historyEnabled {
+                historyQuickMenu
+            }
+
+            Button { showDetails = true } label: {
+                Image(systemName: "list.bullet.indent")
+            }
+            .buttonStyle(.plain)
+            .disabled(!app.player.isReady)
+            .help("Kapitel & Lesezeichen")
+
             statusIndicator
 
             Button {
@@ -235,6 +268,51 @@ struct PlayerBar: View {
         }
     }
 
+    private var detailsButtonVisible: Bool {
+        app.player.isReady
+    }
+
+    private var historyQuickMenu: some View {
+        Menu {
+            let recent = Array(app.history.entries
+                .filter { $0.itemId == app.currentItem?.id && $0.episodeId == app.currentItem?.episodeId }
+                .prefix(5))
+            if recent.isEmpty {
+                Text(String(localized: "history.empty"))
+                    .foregroundStyle(.secondary)
+            } else {
+                ForEach(recent) { entry in
+                    Button {
+                        app.seekAbsolute(entry.position)
+                    } label: {
+                        let timeStr = formatTime(entry.position)
+                        let label = entry.chapterTitle.map { "\($0) · \(timeStr)" } ?? timeStr
+                        Label(label, systemImage: "clock")
+                    }
+                }
+                Divider()
+            }
+            Button {
+                showFullHistory = true
+            } label: {
+                Label(String(localized: "player.history_all"), systemImage: "clock.arrow.circlepath")
+            }
+        } label: {
+            Image(systemName: "clock.arrow.circlepath")
+                #if os(iOS)
+                .font(.system(size: 22))
+                #else
+                .font(.system(size: 16))
+                #endif
+        }
+        #if os(macOS)
+        .menuStyle(.borderlessButton)
+        .fixedSize()
+        #endif
+        .menuIndicator(.hidden)
+        .help(String(localized: "player.history_recent"))
+    }
+
     private var sleepMenu: some View {
         Menu {
             sleepOption(title: "Aus", mode: .off)
@@ -244,6 +322,9 @@ struct PlayerBar: View {
             sleepOption(title: "30 Minuten", mode: .minutes(30))
             sleepOption(title: "1 Stunde", mode: .minutes(60))
             sleepOption(title: endOfPlaybackLabel, mode: .endOfBook)
+            if !(app.currentItem?.chapters.isEmpty ?? true) {
+                sleepOption(title: "Bis Ende des Kapitels", mode: .endOfChapter)
+            }
         } label: {
             Image(systemName: app.player.sleepTimer == .off ? "moon.zzz" : "moon.zzz.fill")
                 #if os(iOS)