docs: update go sdk examples (#1393)

Signed-off-by: Carlos Alexandro Becker <caarlos0@users.noreply.github.com>

cookbook/copilot-sdk/go/recipe/pr-visualization.go

@@ -103,7 +103,7 @@ func main() {
 	cwd, _ := os.Getwd()
 	session, err := client.CreateSession(ctx, &copilot.SessionConfig{
 		OnPermissionRequest: copilot.PermissionHandler.ApproveAll,
-		Model: "gpt-5",
+		Model:               "gpt-5.4",
 		SystemMessage: &copilot.SystemMessageConfig{
 			Content: fmt.Sprintf(`
 <context>
@@ -123,19 +123,15 @@ The current working directory is: %s
 	if err != nil {
 		log.Fatal(err)
 	}
-	defer session.Destroy()
+	defer session.Disconnect()
 
 	// Set up event handling
 	session.On(func(event copilot.SessionEvent) {
-		switch event.Type {
-		case "assistant.message":
-			if event.Data.Content != nil {
-				fmt.Printf("\n🤖 %s\n\n", *event.Data.Content)
-			}
-		case "tool.execution_start":
-			if event.Data.ToolName != nil {
-				fmt.Printf("  ⚙️  %s\n", *event.Data.ToolName)
-			}
+		switch d := event.Data.(type) {
+		case *copilot.AssistantMessageData:
+			fmt.Printf("\n🤖 %s\n\n", d.Content)
+		case *copilot.ToolExecutionStartData:
+			fmt.Printf("  ⚙️  %s\n", d.ToolName)
 		}
 	})