Replace benchmark error dialogs with notifications

DONE.md

@@ -770,6 +770,7 @@ This file tracks completed features, fixes, and milestones.
 - ✅ Made target file size input unit-selectable with numeric-only entry
 - ✅ Prevented snippet runaway bitrates when using Match Source Format
 - ✅ History sidebar refreshes when jobs complete (snippet entries now appear)
+- ✅ Benchmark errors now show non-blocking notifications instead of OK popups
 - ✅ Stabilized video seeking and embedded rendering
 - ✅ Improved player window positioning
 - ✅ Fixed clear video functionality

TODO.md

@@ -44,6 +44,7 @@ This file tracks upcoming features, improvements, and known issues.
   - Audio bitrate estimation when metadata is missing
   - Target size unit selector and numeric entry
   - Snippet history updates in sidebar
+  - Non-blocking benchmark error notifications
 
 ## Priority Features for dev20+
 

main.go

@@ -1789,7 +1789,10 @@ func (s *appState) showBenchmark() {
 				return
 			}
 			logging.Debug(logging.CatSystem, "failed to generate test video: %v", err)
-			dialog.ShowError(fmt.Errorf("failed to generate test video: %w", err), s.window)
+			fyne.CurrentApp().SendNotification(&fyne.Notification{
+				Title:   "Benchmark Error",
+				Content: fmt.Sprintf("Failed to generate test video: %v", err),
+			})
 			s.showMainMenu()
 			return
 		}
@@ -1812,7 +1815,10 @@ func (s *appState) showBenchmark() {
 				return
 			}
 			logging.Debug(logging.CatSystem, "benchmark failed: %v", err)
-			dialog.ShowError(fmt.Errorf("benchmark failed: %w", err), s.window)
+			fyne.CurrentApp().SendNotification(&fyne.Notification{
+				Title:   "Benchmark Error",
+				Content: fmt.Sprintf("Benchmark failed: %v", err),
+			})
 			s.showMainMenu()
 			return
 		}