feat(share): dup-aware interactive save card with AI tag suggestions

Replace the fire-and-forget share toast with an interactive SwiftUI card.
On open it checks linkding's /api/bookmarks/check/ so an already-saved URL
routes to an Update (no more silent duplicates) and a new URL shows a save
form with title, tags, notes, and a read-later toggle.

Tag suggestions are hybrid: fetch the user's existing tag vocabulary
(/api/tags/) and AI tag ideas (/v1/marks/enrich via anonymous device auth),
auto-fill known-vocabulary matches into the field and surface net-new ideas
as tappable chips. Best-effort and non-blocking — failures never block save.

Also:
- Refresh bookmarks when the app returns to the foreground (scenePhase).
- Render bookmark dates as a static relative label instead of the live
  ticking RelativeDateTime timer.
- Share LinkdingAPI/Bookmark/ServerConfig/MarksAuth into the ShareExtension
  target via project.yml (durable across xcodegen regen) and regenerate.

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

ShareExtension/ShareView.swift

@@ -0,0 +1,307 @@
+import SwiftUI
+
+/// Interactive save card shown by the share extension. On open it checks whether
+/// the URL is already bookmarked, then lets the user set/edit tags, notes, and a
+/// read-later flag before saving (new) or updating (existing) — never a duplicate.
+struct ShareView: View {
+    let url: String
+    /// Called when the extension should dismiss. `saved` is true after a successful
+    /// write, false on cancel.
+    let onClose: (_ saved: Bool) -> Void
+
+    @State private var phase: Phase = .loading
+    @State private var existing: Bookmark?
+    @State private var title = ""
+    @State private var tagText = ""
+    @State private var notes = ""
+    @State private var readLater = false
+    @State private var suggestedTags: [String] = []   // linkding auto_tags
+    @State private var knownTags: Set<String> = []     // user's existing vocabulary (lowercased)
+    @State private var aiSuggestions: [String] = []    // net-new AI ideas (not in vocabulary)
+    @State private var suggesting = false
+    @State private var errorMessage = ""
+
+    @FocusState private var tagsFocused: Bool
+
+    private let api: LinkdingAPI?
+
+    init(url: String, onClose: @escaping (_ saved: Bool) -> Void) {
+        self.url = url
+        self.onClose = onClose
+        self.api = ServerConfig.loadShared().map(LinkdingAPI.init)
+    }
+
+    private enum Phase { case loading, editing, saving, done, failed }
+
+    private static let relativeFormatter: RelativeDateTimeFormatter = {
+        let f = RelativeDateTimeFormatter()
+        f.unitsStyle = .abbreviated
+        f.dateTimeStyle = .named
+        return f
+    }()
+
+    var body: some View {
+        VStack {
+            Spacer()
+            card
+                .frame(maxWidth: 460)
+                .padding(.horizontal, 20)
+            Spacer()
+        }
+        .task { await check() }
+    }
+
+    @ViewBuilder
+    private var card: some View {
+        VStack(alignment: .leading, spacing: 16) {
+            switch phase {
+            case .loading:
+                HStack(spacing: 12) {
+                    ProgressView()
+                    Text("Checking…").foregroundStyle(.secondary)
+                }
+                .frame(maxWidth: .infinity, alignment: .center)
+                .padding(.vertical, 24)
+
+            case .editing, .saving:
+                header
+                editor
+                actions
+
+            case .done:
+                statusCard(icon: "checkmark.circle.fill", tint: .green,
+                           text: existing != nil ? "Updated" : "Saved")
+
+            case .failed:
+                statusCard(icon: "xmark.circle.fill", tint: .red,
+                           text: errorMessage.isEmpty ? "Something went wrong" : errorMessage)
+            }
+        }
+        .padding(20)
+        .background(.regularMaterial, in: RoundedRectangle(cornerRadius: 22, style: .continuous))
+        .shadow(color: .black.opacity(0.15), radius: 24, y: 8)
+    }
+
+    // MARK: - Sections
+
+    private var header: some View {
+        VStack(alignment: .leading, spacing: 4) {
+            if let existing {
+                Label {
+                    Text(existing.dateAdded == .distantPast
+                         ? "Already saved"
+                         : "Already saved · \(Self.relativeFormatter.localizedString(for: existing.dateAdded, relativeTo: Date()))")
+                } icon: {
+                    Image(systemName: "checkmark.circle.fill").foregroundStyle(.green)
+                }
+                .font(.subheadline.weight(.semibold))
+            } else {
+                Text("Save bookmark").font(.headline)
+            }
+
+            Text(title.isEmpty ? url : title)
+                .font(.subheadline.weight(.medium))
+                .lineLimit(2)
+            Text(domain)
+                .font(.caption)
+                .foregroundStyle(.secondary)
+        }
+    }
+
+    private var editor: some View {
+        VStack(alignment: .leading, spacing: 14) {
+            VStack(alignment: .leading, spacing: 6) {
+                TextField("Tags (space separated)", text: $tagText)
+                    .textInputAutocapitalization(.never)
+                    .autocorrectionDisabled()
+                    .focused($tagsFocused)
+                    .textFieldStyle(.roundedBorder)
+
+                if suggesting && aiSuggestions.isEmpty {
+                    HStack(spacing: 6) {
+                        ProgressView().controlSize(.small)
+                        Text("Suggesting tags…")
+                            .font(.caption)
+                            .foregroundStyle(.secondary)
+                    }
+                }
+
+                if !suggestionChips.isEmpty {
+                    ScrollView(.horizontal, showsIndicators: false) {
+                        HStack(spacing: 6) {
+                            ForEach(suggestionChips, id: \.tag) { item in
+                                Button { addTag(item.tag) } label: {
+                                    Text(item.isAI ? "✨ \(item.tag)" : "+ \(item.tag)")
+                                        .font(.caption.weight(.medium))
+                                        .padding(.horizontal, 10)
+                                        .padding(.vertical, 5)
+                                        .background((item.isAI ? Color.purple : .blue).opacity(0.12), in: Capsule())
+                                        .foregroundStyle(item.isAI ? Color.purple : .blue)
+                                }
+                                .buttonStyle(.plain)
+                            }
+                        }
+                    }
+                }
+            }
+
+            TextField("Notes", text: $notes, axis: .vertical)
+                .lineLimit(1...3)
+                .textFieldStyle(.roundedBorder)
+
+            Toggle("Read later", isOn: $readLater)
+                .font(.subheadline)
+        }
+    }
+
+    private var actions: some View {
+        HStack(spacing: 12) {
+            Button("Cancel") { onClose(false) }
+                .buttonStyle(.bordered)
+                .frame(maxWidth: .infinity)
+
+            Button {
+                Task { await commit() }
+            } label: {
+                Group {
+                    if phase == .saving { ProgressView().tint(.white) }
+                    else { Text(existing != nil ? "Update" : "Save") }
+                }
+                .frame(maxWidth: .infinity)
+            }
+            .buttonStyle(.borderedProminent)
+            .disabled(phase == .saving)
+        }
+        .padding(.top, 2)
+    }
+
+    private func statusCard(icon: String, tint: Color, text: String) -> some View {
+        HStack(spacing: 10) {
+            Image(systemName: icon).font(.title3).foregroundStyle(tint)
+            Text(text).font(.headline)
+        }
+        .frame(maxWidth: .infinity, alignment: .center)
+        .padding(.vertical, 16)
+    }
+
+    // MARK: - Derived
+
+    private var domain: String { URL(string: url)?.host ?? url }
+
+    /// Tappable suggestion chips: net-new AI ideas (✨) followed by linkding's
+    /// auto_tags (+), excluding anything already in the field, de-duplicated.
+    private var suggestionChips: [(tag: String, isAI: Bool)] {
+        let current = Set(parsedTags.map { $0.lowercased() })
+        var seen = Set<String>()
+        var out: [(tag: String, isAI: Bool)] = []
+        for tag in aiSuggestions + suggestedTags {
+            let key = tag.lowercased()
+            let isAI = aiSuggestions.contains { $0.lowercased() == key }
+            if !current.contains(key) && seen.insert(key).inserted {
+                out.append((tag, isAI))
+            }
+        }
+        return out
+    }
+
+    private var parsedTags: [String] {
+        tagText.split(whereSeparator: { $0 == " " || $0 == "," })
+            .map { String($0) }
+            .filter { !$0.isEmpty }
+    }
+
+    private func addTag(_ tag: String) {
+        let trimmed = tagText.trimmingCharacters(in: .whitespaces)
+        tagText = trimmed.isEmpty ? tag : trimmed + " " + tag
+        tagText += " "
+    }
+
+    // MARK: - Networking
+
+    private func check() async {
+        guard let api else {
+            errorMessage = "Open Marks first"
+            phase = .failed
+            return
+        }
+        do {
+            let result = try await api.checkBookmark(url: url)
+            if let bookmark = result.bookmark {
+                existing = bookmark
+                title = bookmark.displayTitle
+                tagText = bookmark.tagNames.joined(separator: " ")
+                notes = bookmark.description
+                readLater = bookmark.unread
+            } else {
+                title = result.metadata?.title ?? ""
+                suggestedTags = result.autoTags ?? []
+            }
+            phase = .editing
+            await loadSuggestions()
+        } catch {
+            errorMessage = error.localizedDescription
+            phase = .failed
+        }
+    }
+
+    /// Fetches the user's existing tag vocabulary and AI tag ideas in parallel,
+    /// then applies the hybrid behavior: auto-fill suggestions that match the
+    /// existing vocabulary (new bookmarks only), surface the rest as chips.
+    /// Best-effort — never throws, never blocks saving.
+    private func loadSuggestions() async {
+        guard let api else { return }
+        suggesting = true
+        defer { suggesting = false }
+
+        async let vocabTask = api.fetchTags()
+        let ai = await TagSuggester.suggest(url: url, title: title)
+        let vocab = (try? await vocabTask) ?? []
+        knownTags = Set(vocab.map { $0.lowercased() })
+
+        if existing == nil {
+            // Auto-fill AI tags the user already uses; high confidence, low surprise.
+            let current = Set(parsedTags.map { $0.lowercased() })
+            for tag in ai where knownTags.contains(tag.lowercased()) && !current.contains(tag.lowercased()) {
+                addTag(tag)
+            }
+        }
+        // Everything not in the vocabulary becomes a tappable ✨ chip.
+        aiSuggestions = ai.filter { !knownTags.contains($0.lowercased()) }
+    }
+
+    private func commit() async {
+        guard let api else { return }
+        phase = .saving
+        do {
+            if let existing {
+                let update = BookmarkUpdate(
+                    url: existing.url,
+                    title: existing.title,
+                    description: notes,
+                    tagNames: parsedTags,
+                    unread: readLater,
+                    shared: existing.shared
+                )
+                _ = try await api.updateBookmark(id: existing.id, update: update)
+            } else {
+                let create = BookmarkCreate(
+                    url: url,
+                    title: "",
+                    tagNames: parsedTags,
+                    isArchived: false,
+                    unread: readLater,
+                    shared: false
+                )
+                _ = try await api.createBookmark(create)
+            }
+            phase = .done
+            try? await Task.sleep(nanoseconds: 700_000_000)
+            onClose(true)
+        } catch {
+            errorMessage = error.localizedDescription
+            phase = .failed
+            try? await Task.sleep(nanoseconds: 1_600_000_000)
+            onClose(false)
+        }
+    }
+}