added the avatar and the room title as subtitle in the thread timeline as a principal action

also added a fix for the erroneous reply in thread action while in a thread, and also discovered that we can lead align the principal action again on iOS 26 (so it was a beta issue)

ElementX/Sources/Screens/ThreadTimelineScreen/View/ThreadTimelineScreen.swift

@@ -23,8 +23,9 @@ struct ThreadTimelineScreen: View {
         
     var body: some View {
         TimelineView(timelineContext: timelineContext)
-            .navigationTitle("Thread")
+            .navigationTitle(L10n.commonThread)
             .navigationBarTitleDisplayMode(.inline)
+            .toolbar { toolbar }
             .background(.compound.bgCanvasDefault)
             .toolbarBackground(.visible, for: .navigationBar) // Fix the toolbar's background.
             .timelineMediaPreview(viewModel: $context.mediaPreviewViewModel)
@@ -53,6 +54,24 @@ struct ThreadTimelineScreen: View {
         }
     }
     
+    @ToolbarContentBuilder
+    private var toolbar: some ToolbarContent {
+        // .principal + .primaryAction works better than .navigation leading + trailing
+        // as the latter disables interaction in the action button for rooms with long names
+        ToolbarItem(placement: .principal) {
+            RoomHeaderView(roomName: L10n.commonThread,
+                           roomSubtitle: context.viewState.roomTitle,
+                           roomAvatar: context.viewState.roomAvatar,
+                           dmRecipientVerificationState: context.viewState.dmRecipientVerificationState,
+                           mediaProvider: context.mediaProvider)
+                // Using a button stops it from getting truncated in the navigation bar
+                .contentShape(.rect)
+        }
+        if #available(iOS 26, *) {
+            ToolbarSpacer()
+        }
+    }
+    
     private var isAtBottomAndLive: Bool {
         timelineContext.isScrolledToBottom && timelineContext.viewState.timelineState.isLive
     }