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/MarksApp.swift

@@ -38,6 +38,7 @@ struct MainContainer: View {
     @State private var showDeepLinkPlayer = false
     @State private var selectedTab: AppTab = .bookmarks
     @State private var router = IntentRouter.shared
+    @Environment(\.scenePhase) private var scenePhase
 
     init(config: ServerConfig, onDisconnect: @escaping () -> Void) {
         self.config = config
@@ -64,6 +65,13 @@ struct MainContainer: View {
         .task { applyPendingIntent() }
         .onChange(of: router.openBookmarkURL) { _, _ in applyPendingIntent() }
         .onChange(of: router.searchRequest) { _, _ in applyPendingIntent() }
+        .onChange(of: scenePhase) { old, new in
+            // Refresh when returning to the foreground (cold launch is already
+            // covered by BookmarksView's .task, so only react to a real re-entry).
+            if new == .active && old != .active {
+                Task { await viewModel.load() }
+            }
+        }
         .sheet(item: $deepLinkBrowser) { item in
             BrowserView(url: item.url, title: item.url.host ?? "", claude: viewModel.claude, podcastPlayer: viewModel.podcastPlayer)
         }