Fix feels://subscribe deep link on cold launch via app.open()

When XCUITest calls app.open(url), the app relaunches (cold launch) and
onOpenURL doesn't fire reliably. Capture the URL from launch options in
AppDelegate and check it on appear with a short delay to ensure the view
hierarchy is ready for sheet presentation.

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

Shared/AppDelegate.swift

@@ -11,11 +11,16 @@ import UIKit
 import SwiftUI
 
 class AppDelegate: NSObject, UIApplicationDelegate {
+    static var pendingDeepLinkURL: URL?
+
     private let savedOnboardingData = UserDefaultsStore.getOnboarding()
     @AppStorage(UserDefaultsStore.Keys.theme.rawValue, store: GroupUserDefaults.groupDefaults) private var theme: Theme = .system
 
     @MainActor
     func application(_ application: UIApplication, willFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
+        if let url = launchOptions?[.url] as? URL {
+            AppDelegate.pendingDeepLinkURL = url
+        }
         DataController.shared.removeNoForDates()
         DataController.shared.fillInMissingDates()
         UNUserNotificationCenter.current().delegate = self