really disable history nav when completions dialog is open (#50)

internal/app/app.go

@@ -43,6 +43,7 @@ type App struct {
 	
 	// UI state
 	filepickerOpen bool
+	completionDialogOpen bool
 }
 
 func New(ctx context.Context, conn *sql.DB) (*App, error) {
@@ -141,6 +142,16 @@ func (app *App) SetFilepickerOpen(open bool) {
 	app.filepickerOpen = open
 }
 
+// IsCompletionDialogOpen returns whether the completion dialog is currently open
+func (app *App) IsCompletionDialogOpen() bool {
+	return app.completionDialogOpen
+}
+
+// SetCompletionDialogOpen sets the state of the completion dialog
+func (app *App) SetCompletionDialogOpen(open bool) {
+	app.completionDialogOpen = open
+}
+
 // Shutdown performs a clean shutdown of the application
 func (app *App) Shutdown() {
 	// Cancel all watcher goroutines