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/Pages/Admin/Sites.razor

@@ -13,6 +13,7 @@
 @inject NavigationManager NavigationManager
 @inject IJSRuntime JS
 @inject IDialogService Dialog
+@inject Microsoft.Extensions.Logging.ILogger<Sites> Logger
 
 <div class="container-fluid mt-3">
     <div class="d-flex justify-content-between align-items-center mb-3">
@@ -310,8 +311,15 @@
             await JS.InvokeVoidAsync("navigator.clipboard.writeText", text);
             _toast.ShowSuccess("Copied to clipboard.");
         }
-        catch
+        catch (Microsoft.JSInterop.JSDisconnectedException)
         {
+            // Circuit gone — the user has navigated away; nothing to surface.
+        }
+        catch (Microsoft.JSInterop.JSException ex)
+        {
+            // CentralUI-018: a real clipboard failure (e.g. permission denied)
+            // is logged, not silently swallowed.
+            Logger.LogWarning(ex, "Clipboard copy failed.");
             _toast.ShowError("Copy failed.");
         }
     }