fix(central-ui): resolve CentralUI-015..019 — pager windowing, logout CSRF, narrowed catch blocks, coverage; CentralUI-015 re-triaged Won't Fix

src/ScadaLink.CentralUI/Components/Layout/NavMenu.razor

@@ -101,6 +101,9 @@
                 <div class="d-flex justify-content-between align-items-center">
                     <span class="text-light small">@context.User.FindFirst("DisplayName")?.Value</span>
                     <form method="post" action="/auth/logout" data-enhance="false">
+                        @* CentralUI-017: logout is a state-changing POST and is
+                           CSRF-protected — the antiforgery token is required. *@
+                        <AntiforgeryToken />
                         <button type="submit" class="btn btn-outline-light btn-sm py-0 px-2">Sign Out</button>
                     </form>
                 </div>