fix: preserve cause chain when rewrapping name-collision error

shortcuts/application/slash_command_create.go

@@ -82,7 +82,8 @@ var SlashCommandCreate = common.Shortcut{
 			if !runtime.Bool("force") {
 				p, _ := errs.ProblemOf(err)
 				rewrapped := errs.NewAPIError(p.Subtype, "slash command %q already exists", name).
-					WithHint("rerun with --force to update it, or use `lark-cli application +slash-command-update --command %q`", name)
+					WithHint("rerun with --force to update it, or use `lark-cli application +slash-command-update --command %q`", name).
+					WithCause(err)
 				if p.Code != 0 {
 					rewrapped = rewrapped.WithCode(p.Code)
 				}

shortcuts/application/slash_command_create_test.go

@@ -5,6 +5,7 @@ package application
 
 import (
 	"encoding/json"
+	"errors"
 	"strings"
 	"testing"
 
@@ -103,6 +104,13 @@ func TestSlashCommandCreate_ConflictNoForce(t *testing.T) {
 	if !strings.Contains(p.Hint, "--force") || !strings.Contains(p.Hint, "+slash-command-update") {
 		t.Fatalf("hint must offer --force and update, got %q", p.Hint)
 	}
+	var apiErr *errs.APIError
+	if !errors.As(err, &apiErr) {
+		t.Fatalf("rewrapped error must be *errs.APIError, got %T", err)
+	}
+	if errors.Unwrap(apiErr) == nil {
+		t.Fatal("rewrapped conflict error must preserve the original cause via WithCause")
+	}
 }
 
 func TestSlashCommandCreate_ForceConvertsToUpdate(t *testing.T) {