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>

Marks/Views/BookmarkRow.swift

@@ -8,6 +8,15 @@ struct BookmarkRow: View {
     @State private var podcastTapCount = 0
     @State private var podcastCached = false
 
+    /// Compact, static relative date ("6 min ago"). Using a formatter instead of
+    /// `Text(_, style: .relative)` avoids the live per-second ticking timer.
+    private static let relativeFormatter: RelativeDateTimeFormatter = {
+        let f = RelativeDateTimeFormatter()
+        f.unitsStyle = .abbreviated
+        f.dateTimeStyle = .named
+        return f
+    }()
+
     var body: some View {
         VStack(alignment: .leading, spacing: 6) {
             HStack(alignment: .top, spacing: 11) {
@@ -32,7 +41,7 @@ struct BookmarkRow: View {
                     HStack(spacing: 4) {
                         Text(bookmark.domain)
                         Text("·")
-                        Text(bookmark.dateAdded, style: .relative)
+                        Text(Self.relativeFormatter.localizedString(for: bookmark.dateAdded, relativeTo: Date()))
                     }
                     .font(.footnote)
                     .foregroundStyle(.secondary)