feat: added dead link to Board Page, added PageTitle to DeadLink page

Signed-off-by: limited_dev <loginakkisativ@gmail.com>

ImageBoardServerApp/Pages/Basic/BoardPage.razor

@@ -1,6 +1,7 @@
 @page "/{boardTag}/"
-@using ImageBoardServerApp.Data.Repository
 @using System.ComponentModel.DataAnnotations
+@using ImageBoardServerApp.Data.Repository
+@inject NavigationManager navManager
 
 <Board board="@m"/>
 
@@ -16,6 +17,10 @@
     protected override async Task OnParametersSetAsync()
     {
         m = await BoardsRepository.getBoardByTagAsync(boardTag);
+        if (m == null)
+        {
+            navManager.NavigateTo("/sys/dead");
+        }
     }
 
 }

ImageBoardServerApp/Pages/Basic/DeadLink.razor

@@ -1,7 +1,8 @@
 @page "/sys/dead"
-<h3>DeadLink</h3>
+<PageTitle>Dead Link - Bulletboards</PageTitle>
+<h3>404 - Nothing at this address.</h3>
 <img class="deadlink" src="img/static/deadlink/1.png" alt="Img is dead as well"/>
-<span>This link is dead.</span>
+<span>Seems like this link is dead.</span>
 <br/>
 <a href="/">Return home</a>