Let integration tests post a focus event

Lazygit reloads changed config files when its terminal window regains
focus, but the test harness had no way to simulate that focus event, so
the live config-reload path was untestable. Add a focus event to the
replayed-events queue and expose it through the GuiDriver as FocusIn.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

pkg/gocui/gui.go

@@ -103,6 +103,7 @@ type replayedEvents struct {
 	Keys        chan *TcellKeyEventWrapper
 	Resizes     chan *TcellResizeEventWrapper
 	MouseEvents chan *TcellMouseEventWrapper
+	FocusEvents chan *TcellFocusEventWrapper
 }
 
 type RecordingConfig struct {
@@ -245,6 +246,7 @@ func NewGui(opts NewGuiOpts) (*Gui, error) {
 			Keys:        make(chan *TcellKeyEventWrapper),
 			Resizes:     make(chan *TcellResizeEventWrapper),
 			MouseEvents: make(chan *TcellMouseEventWrapper),
+			FocusEvents: make(chan *TcellFocusEventWrapper),
 		}
 	}
 

pkg/gocui/tcell_driver.go

@@ -266,6 +266,22 @@ func (wrapper TcellResizeEventWrapper) toTcellEvent() tcell.Event {
 	return tcell.NewEventResize(wrapper.Width, wrapper.Height)
 }
 
+type TcellFocusEventWrapper struct {
+	Timestamp int64
+	Focused   bool
+}
+
+func NewTcellFocusEventWrapper(event *tcell.EventFocus, timestamp int64) *TcellFocusEventWrapper {
+	return &TcellFocusEventWrapper{
+		Timestamp: timestamp,
+		Focused:   event.Focused,
+	}
+}
+
+func (wrapper TcellFocusEventWrapper) toTcellEvent() tcell.Event {
+	return tcell.NewEventFocus(wrapper.Focused)
+}
+
 // pollEvent get tcell.Event and transform it into gocuiEvent
 func (g *Gui) pollEvent() GocuiEvent {
 	var tev tcell.Event
@@ -277,6 +293,8 @@ func (g *Gui) pollEvent() GocuiEvent {
 			tev = (ev).toTcellEvent()
 		case ev := <-g.ReplayedEvents.MouseEvents:
 			tev = (ev).toTcellEvent()
+		case ev := <-g.ReplayedEvents.FocusEvents:
+			tev = (ev).toTcellEvent()
 		}
 	} else {
 		tev = <-Screen.EventQ()