Podcast UX baseline: mini player during generation, end-of-track reset, library view

- Mini player shows as soon as generation starts (not just when audio ready)
- Idempotency: tapping headphones again during generation is a no-op
- Playback resets to position 0 on completion (standard player behavior)
- Stop button in full player visible during generation
- PodcastLibraryView lists all generated podcasts
- Sparkles menu gains Podcasts entry
- Fix AnalyticsService Sendable error (serialize before Task.detached boundary)

Marks/Services/AnalyticsService.swift

@@ -2,6 +2,10 @@ import Foundation
 
 enum Analytics {
     static func track(_ event: String, _ properties: [String: Any] = [:]) {
+        // Serialize before crossing the task boundary — Data is Sendable, [String: Any] is not
+        var body: [String: Any] = ["event": event]
+        if !properties.isEmpty { body["properties"] = properties }
+        guard let payload = try? JSONSerialization.data(withJSONObject: body) else { return }
         Task.detached {
             do {
                 let token = try await MarksAuth.validToken()
@@ -10,9 +14,7 @@ enum Analytics {
                 request.httpMethod = "POST"
                 request.setValue("Bearer \(token)", forHTTPHeaderField: "Authorization")
                 request.setValue("application/json", forHTTPHeaderField: "Content-Type")
-                var body: [String: Any] = ["event": event]
+                request.httpBody = payload
-                if !properties.isEmpty { body["properties"] = properties }
-                request.httpBody = try JSONSerialization.data(withJSONObject: body)
                 let (_, response) = try await URLSession.shared.data(for: request)
                 let status = (response as? HTTPURLResponse)?.statusCode ?? 0
                 if status < 200 || status > 299 {

Marks/Views/BookmarksView.swift

@@ -11,6 +11,7 @@ struct BookmarksView: View {
     @State private var editingBookmark: Bookmark?
     @State private var browsingBookmark: Bookmark?
     @State private var showFullPlayer = false
+    @State private var showPodcastLibrary = false
     @State private var readingProgress: [String: Double] = ReadingProgress.all()
 
     var body: some View {
@@ -118,6 +119,11 @@ struct BookmarksView: View {
                         } label: {
                             Label("Enrich All with AI", systemImage: "wand.and.stars")
                         }
+                        Button {
+                            showPodcastLibrary = true
+                        } label: {
+                            Label("Podcasts", systemImage: "headphones")
+                        }
                     } label: {
                         Image(systemName: "sparkles")
                     }
@@ -150,7 +156,7 @@ struct BookmarksView: View {
             }
             .overlay(alignment: .bottom) {
                 VStack(spacing: 8) {
-                    if viewModel.podcastPlayer.player != nil {
+                    if !viewModel.podcastPlayer.currentArticleUrl.isEmpty {
                         MiniPlayerView(vm: viewModel.podcastPlayer) {
                             showFullPlayer = true
                         }
@@ -160,7 +166,7 @@ struct BookmarksView: View {
                         enrichmentBanner
                     }
                 }
-                .animation(.spring(duration: 0.3), value: viewModel.podcastPlayer.player != nil)
+                .animation(.spring(duration: 0.3), value: !viewModel.podcastPlayer.currentArticleUrl.isEmpty)
                 .padding(.bottom, 8)
             }
         }
@@ -193,6 +199,9 @@ struct BookmarksView: View {
                 stopOnDismiss: false
             )
         }
+        .sheet(isPresented: $showPodcastLibrary) {
+            PodcastLibraryView(vm: viewModel.podcastPlayer, claude: viewModel.claude)
+        }
         .refreshable {
             await viewModel.load()
         }

Marks/Views/PodcastPlayerView.swift

@@ -43,13 +43,21 @@ final class PodcastPlayerViewModel {
     var currentArticleUrl: String = ""
     var currentArticleTitle: String = ""
 
+    var isGenerating: Bool {
+        switch phase {
+        case .generating, .downloading: return true
+        default: return false
+        }
+    }
+
     private var pollingTask: Task<Void, Never>?
     private var timeObserver: Any?
+    private var endObserver: Any?
     private var currentPodcastTitle: String = "Marks Podcast"
 
     func start(articleUrl: String, articleTitle: String = "", claude: ClaudeService) {
-        // Idempotent — don't restart the same article if already playing
+        // Idempotent — don't restart if already generating or playing this article
-        if currentArticleUrl == articleUrl && player != nil { return }
+        if currentArticleUrl == articleUrl && (player != nil || pollingTask != nil) { return }
 
         // Teardown previous episode (saves its position)
         if player != nil { stop() }
@@ -105,6 +113,8 @@ final class PodcastPlayerViewModel {
         pollingTask?.cancel()
         player?.pause()
         if let obs = timeObserver { player?.removeTimeObserver(obs) }
+        if let obs = endObserver { NotificationCenter.default.removeObserver(obs) }
+        endObserver = nil
         player = nil
         isPlaying = false
         currentTime = 0
@@ -158,6 +168,18 @@ final class PodcastPlayerViewModel {
             }
         }
 
+        // Reset to start when playback finishes, like standard media players
+        endObserver = NotificationCenter.default.addObserver(
+            forName: .AVPlayerItemDidPlayToEndTime, object: item, queue: .main
+        ) { [weak self] _ in
+            guard let self else { return }
+            self.isPlaying = false
+            self.currentTime = 0
+            self.player?.seek(to: .zero)
+            PodcastProgress.set(url: self.currentArticleUrl, time: 0, duration: self.duration)
+            self.updateNowPlaying()
+        }
+
         let interval = CMTime(seconds: 0.5, preferredTimescale: 600)
         timeObserver = p.addPeriodicTimeObserver(forInterval: interval, queue: .main) { [weak self] t in
             guard let self else { return }
@@ -243,7 +265,7 @@ struct PodcastPlayerView: View {
                 ToolbarItem(placement: .topBarLeading) {
                     Button("Done") { dismiss() }
                 }
-                if vm.player != nil {
+                if !vm.currentArticleUrl.isEmpty {
                     ToolbarItem(placement: .topBarTrailing) {
                         Button { vm.stop(); dismiss() } label: {
                             Image(systemName: "stop.circle")
@@ -365,7 +387,7 @@ struct MiniPlayerView: View {
                 Image(systemName: "waveform")
                     .font(.system(size: 16, weight: .semibold))
                     .foregroundStyle(.blue)
-                    .symbolEffect(.variableColor.iterative, isActive: vm.isPlaying)
+                    .symbolEffect(.variableColor.iterative, isActive: vm.isPlaying || vm.isGenerating)
                     .frame(width: 22)
 
                 VStack(alignment: .leading, spacing: 2) {
@@ -380,6 +402,10 @@ struct MiniPlayerView: View {
 
                 Spacer()
 
+                if vm.isGenerating {
+                    ProgressView()
+                        .frame(width: 36, height: 36)
+                } else {
                     Button {
                         vm.togglePlayPause()
                     } label: {
@@ -389,6 +415,7 @@ struct MiniPlayerView: View {
                             .frame(width: 36, height: 36)
                     }
                     .buttonStyle(.plain)
+                }
 
                 Button {
                     vm.stop()
@@ -435,3 +462,62 @@ struct MiniPlayerView: View {
         return mins > 0 ? "\(mins) min left" : "Almost done"
     }
 }
+
+// MARK: - Podcast library
+
+struct PodcastLibraryView: View {
+    let vm: PodcastPlayerViewModel
+    let claude: ClaudeService
+
+    @State private var entries: [PodcastEntry] = []
+    @Environment(\.dismiss) private var dismiss
+
+    var body: some View {
+        NavigationStack {
+            Group {
+                if entries.isEmpty {
+                    ContentUnavailableView(
+                        "No Podcasts",
+                        systemImage: "headphones",
+                        description: Text("Podcasts you generate will appear here.")
+                    )
+                } else {
+                    List(entries) { entry in
+                        HStack(spacing: 12) {
+                            VStack(alignment: .leading, spacing: 4) {
+                                Text(entry.title ?? entry.articleUrl)
+                                    .font(.system(size: 15, weight: .medium))
+                                    .lineLimit(2)
+                                Text(entry.createdAt.formatted(date: .abbreviated, time: .omitted))
+                                    .font(.system(size: 12))
+                                    .foregroundStyle(.secondary)
+                            }
+                            Spacer()
+                            Button {
+                                vm.start(articleUrl: entry.articleUrl,
+                                         articleTitle: entry.title ?? "",
+                                         claude: claude)
+                                dismiss()
+                            } label: {
+                                Image(systemName: "play.circle.fill")
+                                    .font(.system(size: 36))
+                                    .foregroundStyle(.blue)
+                            }
+                            .buttonStyle(.plain)
+                        }
+                        .padding(.vertical, 6)
+                    }
+                    .listStyle(.plain)
+                }
+            }
+            .navigationTitle("Podcasts")
+            .navigationBarTitleDisplayMode(.inline)
+            .toolbar {
+                ToolbarItem(placement: .topBarTrailing) {
+                    Button("Done") { dismiss() }
+                }
+            }
+        }
+        .onAppear { entries = PodcastIndex.all() }
+    }
+}