Fix remaining compiler warnings across solution

- CS8602: Add null-conditional operators for LogService access
- CS0219: Remove unused keyPressed variable in EventCancellationTests
- CS8625: Replace null ScrollToControl call with direct ScrollOffset set

Author: nickprotop

Examples/MultiDashboard/Windows/LogStreamWindow.cs

@@ -64,7 +64,7 @@ private async Task UpdateLoopAsync(Window window, CancellationToken ct)
                 var level = levels[counter % 4];
                 var message = _logService.GenerateRandomLog();
 
-                _windowSystem.LogService.Log(level, message, "MultiDashboard");
+                _windowSystem?.LogService?.Log(level, message, "MultiDashboard");
 
                 counter++;
                 await Task.Delay(500, ct);
@@ -75,7 +75,7 @@ private async Task UpdateLoopAsync(Window window, CancellationToken ct)
             }
             catch (Exception ex)
             {
-                _windowSystem?.LogService.LogError("Log stream error", ex, "LogStream");
+                _windowSystem?.LogService?.LogError("Log stream error", ex, "LogStream");
             }
         }
     }

SharpConsoleUI.Tests/InputHandling/EventCancellationTests.cs

@@ -264,8 +264,7 @@ public void MinimizedWindow_DoesNotReceiveKeyboardInput()
 
         window.Minimize();
 
-        bool keyPressed = false;
-        window.KeyPressed += (s, e) => keyPressed = true;
+        window.KeyPressed += (s, e) => { };
 
         var keyInfo = new ConsoleKeyInfo('X', ConsoleKey.X, false, false, false);
         system.InputStateService.EnqueueKey(keyInfo);

SharpConsoleUI.Tests/InputHandling/ShortcutsTests.cs

@@ -352,7 +352,7 @@ public void Home_ScrollsToTop()
         }
 
         system.WindowStateService.AddWindow(window);
-        window.ScrollToControl(null); // Scroll down
+        window.ScrollOffset = 20; // Scroll down
 
         var homeKey = new ConsoleKeyInfo('\0', ConsoleKey.Home, false, false, false);
         system.InputStateService.EnqueueKey(homeKey);