feat: implement identity authentication, authorization policies, and MAUI platform support with Docker orchestration

src/NexusReader.UI.Shared/Services/ReaderNavigationService.cs

@@ -1,3 +1,5 @@
+using System.Linq;
+
 namespace NexusReader.UI.Shared.Services;
 
 public class ReaderNavigationService : IReaderNavigationService
@@ -6,29 +8,29 @@ public class ReaderNavigationService : IReaderNavigationService
     public int TotalChapters { get; private set; } = 1;
     public string ChapterTitle { get; private set; } = "Loading...";
 
-    public event Action? OnNavigationChanged;
+    public event Func<Task>? OnNavigationChanged;
 
-    public void GoToChapter(int index)
+    public async Task GoToChapter(int index)
     {
         if (index < 0 || index >= TotalChapters) return;
         
         CurrentChapterIndex = index;
-        OnNavigationChanged?.Invoke();
+        await NotifyNavigationChangedAsync();
     }
 
-    public void GoToNextChapter()
+    public async Task GoToNextChapter()
     {
         if (CurrentChapterIndex < TotalChapters - 1)
         {
-            GoToChapter(CurrentChapterIndex + 1);
+            await GoToChapter(CurrentChapterIndex + 1);
         }
     }
 
-    public void GoToPreviousChapter()
+    public async Task GoToPreviousChapter()
     {
         if (CurrentChapterIndex > 0)
         {
-            GoToChapter(CurrentChapterIndex - 1);
+            await GoToChapter(CurrentChapterIndex - 1);
         }
     }
 
@@ -41,7 +43,21 @@ public class ReaderNavigationService : IReaderNavigationService
         
         if (changed)
         {
-            OnNavigationChanged?.Invoke();
+            // Note: UpdateMetadata remains void, so we trigger notification fire-and-forget here
+            // but usually this is called during a render cycle where metadata is updated from a load.
+            _ = NotifyNavigationChangedAsync();
+        }
+    }
+
+    private async Task NotifyNavigationChangedAsync()
+    {
+        var handlers = OnNavigationChanged?.GetInvocationList();
+        if (handlers != null)
+        {
+            foreach (var handler in handlers.Cast<Func<Task>>())
+            {
+                await handler();
+            }
         }
     }
 }