Replace Flutter app with native SwiftUI rewrite (iOS 26)

Complete ground-up rewrite in SwiftUI targeting iOS 26. Drops the Flutter/Dart
codebase entirely in favour of a lean native app with no third-party dependencies.

Features shipped:
- Bookmark list with pagination, pull-to-refresh, swipe delete/archive
- Add bookmark form + iOS share extension (zero-tap save from any app)
- Tags tab — all tags sorted by count, tap to browse filtered bookmarks
- Native search tab (Tab role: .search) with instant client-side filtering
- AI enrichment via OpenRouter (google/gemini-2.0-flash-lite-001): auto-summary
  and tag generation, semantic search, smart collections
- Settings: linkding server config, OpenRouter API key
- App Groups for credential sharing between main app and share extension
- Swift 6 strict concurrency throughout (@Observable, @MainActor)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ShareExtension/ShareViewController.swift

@@ -0,0 +1,129 @@
+import UIKit
+import UniformTypeIdentifiers
+
+@objc(ShareViewController)
+class ShareViewController: UIViewController {
+
+    private let appGroupId = "group.com.magicive.marks"
+    private let configKey = "serverConfig"
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        let blur = UIVisualEffectView(effect: UIBlurEffect(style: .systemMaterial))
+        blur.frame = view.bounds
+        blur.autoresizingMask = [.flexibleWidth, .flexibleHeight]
+        view.addSubview(blur)
+        extractURLAndSave()
+    }
+
+    private func extractURLAndSave() {
+        guard let item = extensionContext?.inputItems.first as? NSExtensionItem,
+              let attachments = item.attachments else {
+            showResult(success: false, message: "Nothing to save")
+            return
+        }
+
+        func load(typeId: String) -> Bool {
+            guard let attachment = attachments.first(where: { $0.hasItemConformingToTypeIdentifier(typeId) }) else {
+                return false
+            }
+            attachment.loadItem(forTypeIdentifier: typeId, options: nil) { [weak self] item, _ in
+                let urlString = typeId == UTType.url.identifier
+                    ? ((item as? URL)?.absoluteString ?? (item as? String))
+                    : (item as? String)
+                DispatchQueue.main.async {
+                    if let url = urlString { self?.save(url: url) }
+                    else { self?.showResult(success: false, message: "No URL found") }
+                }
+            }
+            return true
+        }
+
+        if !load(typeId: UTType.url.identifier) && !load(typeId: UTType.plainText.identifier) {
+            showResult(success: false, message: "No URL found")
+        }
+    }
+
+    private func save(url: String) {
+        guard let groupDefaults = UserDefaults(suiteName: appGroupId),
+              let data = groupDefaults.data(forKey: configKey),
+              let config = try? JSONSerialization.jsonObject(with: data) as? [String: Any],
+              let host = config["host"] as? String,
+              let token = config["token"] as? String,
+              let useHttps = config["useHttps"] as? Bool else {
+            showResult(success: false, message: "Open Marks first")
+            return
+        }
+
+        var base = (useHttps ? "https" : "http") + "://" + host
+        if let port = config["port"] as? Int { base += ":\(port)" }
+        if let path = config["path"] as? String, !path.isEmpty { base += path }
+
+        guard let apiUrl = URL(string: "\(base)/api/bookmarks/") else {
+            showResult(success: false, message: "Bad server URL")
+            return
+        }
+
+        var req = URLRequest(url: apiUrl)
+        req.httpMethod = "POST"
+        req.setValue("Token \(token)", forHTTPHeaderField: "Authorization")
+        req.setValue("application/json", forHTTPHeaderField: "Content-Type")
+        req.httpBody = try? JSONSerialization.data(withJSONObject: [
+            "url": url, "is_archived": false, "unread": false, "shared": false
+        ])
+
+        URLSession.shared.dataTask(with: req) { [weak self] _, response, error in
+            DispatchQueue.main.async {
+                let code = (response as? HTTPURLResponse)?.statusCode ?? 0
+                let ok = error == nil && (code == 200 || code == 201)
+                self?.showResult(success: ok, message: ok ? "Bookmarked" : "Failed to save")
+            }
+        }.resume()
+    }
+
+    private func showResult(success: Bool, message: String) {
+        let card = UIView()
+        card.backgroundColor = success ? .systemGreen : .systemRed
+        card.layer.cornerRadius = 16
+        card.layer.cornerCurve = .continuous
+        card.translatesAutoresizingMaskIntoConstraints = false
+        card.alpha = 0
+
+        let stack = UIStackView()
+        stack.axis = .horizontal
+        stack.spacing = 10
+        stack.alignment = .center
+        stack.translatesAutoresizingMaskIntoConstraints = false
+
+        let icon = UIImageView(image: UIImage(systemName: success ? "checkmark.circle.fill" : "xmark.circle.fill"))
+        icon.tintColor = .white
+        icon.preferredSymbolConfiguration = .init(pointSize: 22, weight: .semibold)
+
+        let label = UILabel()
+        label.text = message
+        label.textColor = .white
+        label.font = .systemFont(ofSize: 17, weight: .semibold)
+
+        stack.addArrangedSubview(icon)
+        stack.addArrangedSubview(label)
+        card.addSubview(stack)
+        view.addSubview(card)
+
+        NSLayoutConstraint.activate([
+            stack.centerXAnchor.constraint(equalTo: card.centerXAnchor),
+            stack.centerYAnchor.constraint(equalTo: card.centerYAnchor),
+            stack.leadingAnchor.constraint(greaterThanOrEqualTo: card.leadingAnchor, constant: 24),
+            card.centerXAnchor.constraint(equalTo: view.centerXAnchor),
+            card.centerYAnchor.constraint(equalTo: view.centerYAnchor),
+            card.heightAnchor.constraint(equalToConstant: 56),
+            card.widthAnchor.constraint(greaterThanOrEqualToConstant: 180),
+        ])
+
+        UIView.animate(withDuration: 0.2) { card.alpha = 1 }
+        DispatchQueue.main.asyncAfter(deadline: .now() + (success ? 0.8 : 2.0)) { [weak self] in
+            UIView.animate(withDuration: 0.15, animations: { card.alpha = 0 }) { _ in
+                self?.extensionContext?.completeRequest(returningItems: [], completionHandler: nil)
+            }
+        }
+    }
+}