fix(api): return correct http code on assets api (#6388)

* fix(api): return correct http code on assets api

* add test

* fix test

internal/api/http/error.go

@@ -0,0 +1,47 @@
+package http
+
+import (
+	"errors"
+	"net/http"
+
+	caos_errs "github.com/zitadel/zitadel/internal/errors"
+)
+
+func ZitadelErrorToHTTPStatusCode(err error) (statusCode int, ok bool) {
+	if err == nil {
+		return http.StatusOK, true
+	}
+	//nolint:errorlint
+	switch err.(type) {
+	case *caos_errs.AlreadyExistsError:
+		return http.StatusConflict, true
+	case *caos_errs.DeadlineExceededError:
+		return http.StatusGatewayTimeout, true
+	case *caos_errs.InternalError:
+		return http.StatusInternalServerError, true
+	case *caos_errs.InvalidArgumentError:
+		return http.StatusBadRequest, true
+	case *caos_errs.NotFoundError:
+		return http.StatusNotFound, true
+	case *caos_errs.PermissionDeniedError:
+		return http.StatusForbidden, true
+	case *caos_errs.PreconditionFailedError:
+		// use the same code as grpc-gateway:
+		// https://github.com/grpc-ecosystem/grpc-gateway/blob/9e33e38f15cb7d2f11096366e62ea391a3459ba9/runtime/errors.go#L59
+		return http.StatusBadRequest, true
+	case *caos_errs.UnauthenticatedError:
+		return http.StatusUnauthorized, true
+	case *caos_errs.UnavailableError:
+		return http.StatusServiceUnavailable, true
+	case *caos_errs.UnimplementedError:
+		return http.StatusNotImplemented, true
+	case *caos_errs.ResourceExhaustedError:
+		return http.StatusTooManyRequests, true
+	default:
+		c := new(caos_errs.CaosError)
+		if errors.As(err, &c) {
+			return ZitadelErrorToHTTPStatusCode(errors.Unwrap(err))
+		}
+		return http.StatusInternalServerError, false
+	}
+}