Fix A11y tests (#5104)

* replace NavigationStack with ElementNavigationStack to allow the content to be rendered without a NavigationStack in a11y tests

* fix a11y tests

* update xcodeproject

* swiftformat fix

* use iOS 26.1 for CI

* use a wrapper to solve the issue for a11y tests

* ElementNavigationStack only uses the trick in DEBUG mode, and added a swiftlint rule to prevent the usage of NavigationStack

ElementX/Sources/Screens/RoomScreen/View/RoomScreen.swift

@@ -201,14 +201,14 @@ struct RoomScreen_Previews: PreviewProvider, TestablePreview {
     static let tombstonedViewModels = makeViewModels(hasSuccessor: true)
 
     static var previews: some View {
-        NavigationStack {
+        ElementNavigationStack {
             RoomScreen(context: viewModels.room.context,
                        timelineContext: viewModels.timeline.context,
                        composerToolbar: ComposerToolbar.mock())
         }
         .previewDisplayName("Normal")
         
-        NavigationStack {
+        ElementNavigationStack {
             RoomScreen(context: readOnlyViewModels.room.context,
                        timelineContext: readOnlyViewModels.timeline.context,
                        composerToolbar: ComposerToolbar.mock())
@@ -216,7 +216,7 @@ struct RoomScreen_Previews: PreviewProvider, TestablePreview {
         .previewDisplayName("Read-only")
         .snapshotPreferences(expect: readOnlyViewModels.room.context.$viewState.map { !$0.canSendMessage })
         
-        NavigationStack {
+        ElementNavigationStack {
             RoomScreen(context: tombstonedViewModels.room.context,
                        timelineContext: tombstonedViewModels.timeline.context,
                        composerToolbar: ComposerToolbar.mock())

ElementX/Sources/Screens/RoomScreen/View/SwipeRightAction.swift

@@ -171,7 +171,7 @@ struct SwipeRightAction_Previews: PreviewProvider, TestablePreview {
         @State private var isPresentingSheet = false
         
         var body: some View {
-            NavigationStack {
+            ElementNavigationStack {
                 ScrollView {
                     VStack(alignment: .leading, spacing: 2) {
                         Text("This is a message from somebody with a couple of lines of text.")