feat(podcasts): #8 follow-ups — AI summary + in-app Open Bookmark

Resolves the two deviations from the episode detail sheet:

- AI summary now shows in the detail sheet. Added a URL-keyed AISummaryStore
  that BookmarksViewModel populates as it enriches/loads bookmarks, so the
  decoupled Podcasts tab can surface a summary from just the episode URL —
  without recoupling to BookmarksViewModel.
- "Open Bookmark" opens the in-app BrowserView as a nested sheet (generator
  threaded through PodcastLibraryView / EpisodePickerView), alongside the
  existing "Open in Safari" and Share.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Marks/MarksApp.swift

@@ -57,7 +57,7 @@ struct MainContainer: View {
                 TagsView(viewModel: viewModel)
             }
             Tab("Podcasts", systemImage: "headphones", value: AppTab.podcasts) {
-                PodcastLibraryView(vm: viewModel.podcastPlayer, claude: viewModel.claude)
+                PodcastLibraryView(vm: viewModel.podcastPlayer, claude: viewModel.claude, podcastGenerator: viewModel.podcastGenerator)
             }
             .badge(library.unplayedCount)
             Tab(value: AppTab.search, role: .search) {

Marks/Services/AISummaryStore.swift

@@ -0,0 +1,27 @@
+import Foundation
+
+/// URL-keyed cache of AI summaries so views that only know a URL — e.g. the
+/// deliberately-decoupled Podcasts tab — can show a bookmark's summary without
+/// holding the full `Bookmark`. Written by `BookmarksViewModel` as it enriches
+/// and loads bookmarks; read by the episode detail sheet.
+enum AISummaryStore {
+    private static let key = "aiSummaryByURL"
+
+    static func summary(for url: String) -> String? {
+        let store = UserDefaults.standard.dictionary(forKey: key) as? [String: String] ?? [:]
+        let value = store[url]
+        return (value?.isEmpty ?? true) ? nil : value
+    }
+
+    static func set(_ summary: String?, for url: String) {
+        var store = UserDefaults.standard.dictionary(forKey: key) as? [String: String] ?? [:]
+        if let summary, !summary.isEmpty {
+            guard store[url] != summary else { return }   // no-op if unchanged
+            store[url] = summary
+        } else {
+            guard store[url] != nil else { return }
+            store.removeValue(forKey: url)
+        }
+        UserDefaults.standard.set(store, forKey: key)
+    }
+}

Marks/Views/BookmarkListRow.swift

@@ -85,7 +85,7 @@ struct BookmarkListRow: View {
             )
         }
         .sheet(item: $episodePickerBookmark) { b in
-            EpisodePickerView(bookmark: b, vm: viewModel.podcastPlayer, claude: viewModel.claude)
+            EpisodePickerView(bookmark: b, vm: viewModel.podcastPlayer, claude: viewModel.claude, podcastGenerator: viewModel.podcastGenerator)
         }
     }
 

Marks/Views/BookmarksViewModel.swift

@@ -299,6 +299,8 @@ final class BookmarksViewModel {
             "tags": bookmark.aiTags ?? []
         ]
         UserDefaults.standard.set(store, forKey: "aiData")
+        // Mirror by URL so the decoupled Podcasts tab can show summaries.
+        AISummaryStore.set(bookmark.aiSummary, for: bookmark.url)
     }
 
     private func restoreAIData() {
@@ -311,6 +313,8 @@ final class BookmarksViewModel {
             if let d = store["\(list[i].id)"] {
                 list[i].aiSummary = (d["summary"] as? String).flatMap { $0.isEmpty ? nil : $0 }
                 list[i].aiTags = d["tags"] as? [String]
+                // Keep the URL-keyed summary cache populated for existing bookmarks.
+                if let summary = list[i].aiSummary { AISummaryStore.set(summary, for: list[i].url) }
             }
         }
     }

Marks/Views/PodcastPlayerView.swift

@@ -797,6 +797,7 @@ struct MiniPlayerView: View {
 struct PodcastLibraryView: View {
     let vm: PodcastPlayerViewModel
     let claude: ClaudeService
+    let podcastGenerator: PodcastGenerationManager
 
     @State private var library = PodcastLibrary.shared
     @State private var showFullPlayer = false
@@ -858,7 +859,7 @@ struct PodcastLibraryView: View {
                 )
             }
             .sheet(item: $detailEntry) { entry in
-                EpisodeDetailView(entry: entry, vm: vm, claude: claude)
+                EpisodeDetailView(entry: entry, vm: vm, claude: claude, podcastGenerator: podcastGenerator)
             }
         }
         .onAppear { library.reload() }
@@ -979,6 +980,7 @@ struct EpisodePickerView: View {
     let bookmark: Bookmark
     let vm: PodcastPlayerViewModel
     let claude: ClaudeService
+    let podcastGenerator: PodcastGenerationManager
 
     @State private var entries: [PodcastEntry] = []
     @State private var detailEntry: PodcastEntry?
@@ -1035,7 +1037,7 @@ struct EpisodePickerView: View {
                 }
             }
             .sheet(item: $detailEntry) { entry in
-                EpisodeDetailView(entry: entry, vm: vm, claude: claude)
+                EpisodeDetailView(entry: entry, vm: vm, claude: claude, podcastGenerator: podcastGenerator)
             }
         }
         .onAppear { entries = PodcastIndex.find(for: bookmark.url) }
@@ -1057,10 +1059,12 @@ struct EpisodeDetailView: View {
     let entry: PodcastEntry
     let vm: PodcastPlayerViewModel
     let claude: ClaudeService
+    let podcastGenerator: PodcastGenerationManager
 
     @Environment(\.dismiss) private var dismiss
     @Environment(\.openURL) private var openURL
     @State private var library = PodcastLibrary.shared
+    @State private var showBrowser = false
 
     private var isCurrent: Bool { vm.currentArticleUrl == entry.articleUrl }
     private var isPlayed: Bool {
@@ -1068,6 +1072,10 @@ struct EpisodeDetailView: View {
     }
     private var sourceURL: URL? { URL(string: entry.parentBookmarkUrl ?? entry.articleUrl) }
     private var domain: String { URL(string: entry.articleUrl)?.host ?? entry.articleUrl }
+    private var summary: String? {
+        AISummaryStore.summary(for: entry.parentBookmarkUrl ?? entry.articleUrl)
+            ?? AISummaryStore.summary(for: entry.articleUrl)
+    }
 
     var body: some View {
         NavigationStack {
@@ -1094,6 +1102,14 @@ struct EpisodeDetailView: View {
                     .padding(.vertical, 4)
                 }
 
+                if let summary {
+                    Section("Summary") {
+                        Text(summary)
+                            .font(.subheadline)
+                            .foregroundStyle(.secondary)
+                    }
+                }
+
                 Section {
                     Button {
                         if isCurrent {
@@ -1116,10 +1132,15 @@ struct EpisodeDetailView: View {
 
                 if let sourceURL {
                     Section {
+                        Button {
+                            showBrowser = true
+                        } label: {
+                            Label("Open Bookmark", systemImage: "book")
+                        }
                         Button {
                             openURL(sourceURL)
                         } label: {
-                            Label("Open Source", systemImage: "safari")
+                            Label("Open in Safari", systemImage: "safari")
                         }
                         ShareLink(item: sourceURL) {
                             Label("Share Episode", systemImage: "square.and.arrow.up")
@@ -1144,6 +1165,15 @@ struct EpisodeDetailView: View {
                     Button("Done") { dismiss() }
                 }
             }
+            .sheet(isPresented: $showBrowser) {
+                if let sourceURL {
+                    BrowserView(url: sourceURL,
+                                title: entry.title ?? domain,
+                                claude: claude,
+                                podcastPlayer: vm,
+                                podcastGenerator: podcastGenerator)
+                }
+            }
         }
     }
 }