Add history entry delete button and fix Convert module crash

Features:
- Add "×" delete button to each history entry in sidebar
- Click to remove individual entries from history
- Automatically saves and refreshes sidebar after deletion

Bug Fixes:
- Fix nil pointer crash when opening Convert module
- Fixed widget initialization order: bitrateContainer now created
  AFTER bitratePresetSelect is initialized
- Prevented "invalid memory address" panic in tabs layout

Technical Details:
- Added deleteHistoryEntry() method to remove entries by ID
- Updated BuildHistorySidebar signature to accept onEntryDelete callback
- Moved bitrateContainer creation from line 5742 to 5794
- All Select widgets now properly initialized before container creation

The crash was caused by bitrateContainer containing a nil
bitratePresetSelect widget, which crashed when Fyne's layout system
called .Visible() during tab initialization.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

internal/ui/mainmenu.go

@@ -154,6 +154,7 @@ func sortedKeys(m map[string][]fyne.CanvasObject) []string {
 func BuildHistorySidebar(
 	entries []HistoryEntry,
 	onEntryClick func(HistoryEntry),
+	onEntryDelete func(HistoryEntry),
 	titleColor, bgColor, textColor color.Color,
 ) fyne.CanvasObject {
 	// Filter by status
@@ -167,8 +168,8 @@ func BuildHistorySidebar(
 	}
 
 	// Build lists
-	completedList := buildHistoryList(completedEntries, onEntryClick, bgColor, textColor)
+	completedList := buildHistoryList(completedEntries, onEntryClick, onEntryDelete, bgColor, textColor)
-	failedList := buildHistoryList(failedEntries, onEntryClick, bgColor, textColor)
+	failedList := buildHistoryList(failedEntries, onEntryClick, onEntryDelete, bgColor, textColor)
 
 	// Tabs
 	tabs := container.NewAppTabs(
@@ -193,6 +194,7 @@ func BuildHistorySidebar(
 func buildHistoryList(
 	entries []HistoryEntry,
 	onEntryClick func(HistoryEntry),
+	onEntryDelete func(HistoryEntry),
 	bgColor, textColor color.Color,
 ) *fyne.Container {
 	if len(entries) == 0 {
@@ -201,7 +203,7 @@ func buildHistoryList(
 
 	var items []fyne.CanvasObject
 	for _, entry := range entries {
-		items = append(items, buildHistoryItem(entry, onEntryClick, bgColor, textColor))
+		items = append(items, buildHistoryItem(entry, onEntryClick, onEntryDelete, bgColor, textColor))
 	}
 	return container.NewVBox(items...)
 }
@@ -209,11 +211,21 @@ func buildHistoryList(
 func buildHistoryItem(
 	entry HistoryEntry,
 	onEntryClick func(HistoryEntry),
+	onEntryDelete func(HistoryEntry),
 	bgColor, textColor color.Color,
 ) fyne.CanvasObject {
 	// Badge
 	badge := BuildModuleBadge(entry.Type)
 
+	// Capture entry for closures
+	capturedEntry := entry
+
+	// Delete button - small "×" button
+	deleteBtn := widget.NewButton("×", func() {
+		onEntryDelete(capturedEntry)
+	})
+	deleteBtn.Importance = widget.LowImportance
+
 	// Title
 	titleLabel := widget.NewLabel(utils.ShortenMiddle(entry.Title, 25))
 	titleLabel.TextStyle = fyne.TextStyle{Bold: true}
@@ -234,7 +246,7 @@ func buildHistoryItem(
 	content := container.NewBorder(
 		nil, nil, statusRect, nil,
 		container.NewVBox(
-			container.NewHBox(badge, layout.NewSpacer()),
+			container.NewHBox(badge, layout.NewSpacer(), deleteBtn),
 			titleLabel,
 			timeLabel,
 		),
@@ -245,7 +257,5 @@ func buildHistoryItem(
 
 	item := container.NewPadded(container.NewMax(card, content))
 
-	// Capture entry for closure
-	capturedEntry := entry
 	return NewTappable(item, func() { onEntryClick(capturedEntry) })
 }

main.go

@@ -910,8 +910,8 @@ Config:
 
 	// Layout: details at top (scrollable), FFmpeg at bottom (fixed)
 	content := container.NewBorder(
-		detailsScroll,             // Top: job details (scrollable, takes priority)
+		detailsScroll, // Top: job details (scrollable, takes priority)
-		container.NewVBox(         // Bottom: FFmpeg command (fixed)
+		container.NewVBox( // Bottom: FFmpeg command (fixed)
 			ffmpegSection,
 			container.NewHBox(buttons...),
 		),
@@ -925,6 +925,26 @@ Config:
 	d.Show()
 }
 
+func (s *appState) deleteHistoryEntry(entry ui.HistoryEntry) {
+	// Remove entry from history
+	var updated []ui.HistoryEntry
+	for _, e := range s.historyEntries {
+		if e.ID != entry.ID {
+			updated = append(updated, e)
+		}
+	}
+	s.historyEntries = updated
+
+	// Save updated history
+	cfg := historyConfig{Entries: s.historyEntries}
+	if err := saveHistoryConfig(cfg); err != nil {
+		logging.Debug(logging.CatUI, "failed to save history after delete: %v", err)
+	}
+
+	// Refresh main menu to update sidebar
+	s.showMainMenu()
+}
+
 func (s *appState) stopPreview() {
 	if s.anim != nil {
 		s.anim.Stop()
@@ -1349,6 +1369,7 @@ func (s *appState) showMainMenu() {
 		sidebar = ui.BuildHistorySidebar(
 			s.historyEntries,
 			s.showHistoryDetails,
+			s.deleteHistoryEntry,
 			titleColor,
 			utils.MustHex("#1A1F2E"),
 			textColor,
@@ -5712,18 +5733,13 @@ func buildConvertView(state *appState, src *videoSource) fyne.CanvasObject {
 		}
 	}
 
-	// Create containers for hideable sections
+	// Create CRF container (crfEntry already initialized)
 	crfContainer = container.NewVBox(
 		widget.NewLabelWithStyle("Manual CRF (overrides Quality preset)", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
 		crfEntry,
 	)
 
-	bitrateContainer = container.NewVBox(
+	// Note: bitrateContainer creation moved below after bitratePresetSelect is initialized
-		widget.NewLabelWithStyle("Video Bitrate (for CBR/VBR)", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
-		videoBitrateEntry,
-		widget.NewLabelWithStyle("Recommended Bitrate Preset", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
-		bitratePresetSelect,
-	)
 
 	type bitratePreset struct {
 		Label   string
@@ -5775,6 +5791,14 @@ func buildConvertView(state *appState, src *videoSource) fyne.CanvasObject {
 	})
 	simpleBitrateSelect.SetSelected(state.convert.BitratePreset)
 
+	// Create bitrate container now that bitratePresetSelect is initialized
+	bitrateContainer = container.NewVBox(
+		widget.NewLabelWithStyle("Video Bitrate (for CBR/VBR)", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
+		videoBitrateEntry,
+		widget.NewLabelWithStyle("Recommended Bitrate Preset", fyne.TextAlignLeading, fyne.TextStyle{Bold: true}),
+		bitratePresetSelect,
+	)
+
 	// Simple resolution selector (separate widget to avoid double-parent issues)
 	resolutionSelectSimple := widget.NewSelect([]string{
 		"Source", "360p", "480p", "540p", "720p", "1080p", "1440p", "4K", "8K",