Phase 0 (T1-3/4/7/9/11): find bar w/ native Find API + search engine + site zoom + force reload + F11, wired into MainWindow, E2E smoke (39 tests)

VideoDownloader.Tests/E2E/MainWindowSmokeE2ETests.cs

@@ -0,0 +1,58 @@
+using System.Windows;
+using VideoDownloader.App;
+using VideoDownloader.Tests.Infrastructure;
+
+namespace VideoDownloader.Tests.E2E;
+
+/// <summary>
+/// E2E 스모크: 실제 MainWindow 를 기동해 WebView2 초기화·탐색·검색 바·전체화면 전환이
+/// 크래시 없이 동작하는지 검증한다(Phase 0 통합 확인). 네트워크 의존 제거를 위해 about:blank 사용.
+/// </summary>
+[Collection("E2E")]
+public class MainWindowSmokeE2ETests
+{
+    [Fact]
+    public async Task MainWindow_기동_탐색_검색바_전체화면_스모크()
+    {
+        using var sta = StaDispatcher.Start();
+        WpfTestApp.Ensure(sta.Dispatcher);
+        var ok = await sta.InvokeAsync(async () =>
+        {
+            var window = new MainWindow();
+            window.Show();
+
+            // WebView2 초기화 대기 (Loaded → InitializeBrowserAsync)
+            var cv = await Wait.Until(
+                () => Task.FromResult(window.Browser.CoreWebView2),
+                c => c != null, 30000);
+
+            // about:blank 탐색 (네트워크 불필요)
+            window.NavigateTo("about:blank");
+            await Wait.Until(
+                () => Task.FromResult(cv.Source ?? ""),
+                s => s.Contains("about:blank"), 15000);
+
+            // T1-3 검색 바 열기/닫기
+            window.OpenFind();
+            var findVisible = window.FindBar.Visibility == Visibility.Visible;
+            window.CloseFind();
+            var findCollapsed = window.FindBar.Visibility == Visibility.Collapsed;
+
+            // T1-11 전체화면 토글
+            window.ToggleFullscreen();
+            var toolbarHidden = window.ToolbarRow.Visibility == Visibility.Collapsed;
+            window.ToggleFullscreen();
+            var toolbarBack = window.ToolbarRow.Visibility == Visibility.Visible;
+
+            window.Close();
+            return (init: cv != null, nav: true, findVisible, findCollapsed, toolbarHidden, toolbarBack);
+        });
+
+        Assert.True(ok.init, "WebView2 초기화 실패");
+        Assert.True(ok.nav);
+        Assert.True(ok.findVisible, "검색 바 미표시");
+        Assert.True(ok.findCollapsed, "검색 바 미닫힘");
+        Assert.True(ok.toolbarHidden, "전체화면에서 툴바 미숨김");
+        Assert.True(ok.toolbarBack, "전체화면 복원 실패");
+    }
+}