test: add unit tests for catalog commands

Add command-level tests for catalog search and show:
- Test authentication requirement (no auth errors)
- Test required arguments (query for search, uuid for show)
- Tests validate error messages guide users to 'mxcli auth login'

Catalog client and types tests were already present in the codebase.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: dionesiusap

cmd/mxcli/cmd_catalog_test.go

@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"bytes"
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/spf13/cobra"
+)
+
+// runCatalog executes the catalog subtree with the given args.
+func runCatalog(t *testing.T, args ...string) (string, error) {
+	t.Helper()
+	for _, c := range []*cobra.Command{catalogSearchCmd, catalogShowCmd} {
+		resetCmdFlags(c)
+	}
+
+	var out bytes.Buffer
+	rootCmd.SetOut(&out)
+	rootCmd.SetErr(&out)
+	rootCmd.SetArgs(append([]string{"catalog"}, args...))
+	err := rootCmd.ExecuteContext(context.Background())
+	return out.String(), err
+}
+
+func TestCatalogSearch_NoAuth(t *testing.T) {
+	withTestHome(t)
+
+	_, err := runCatalog(t, "search", "test")
+	if err == nil {
+		t.Fatal("expected error when not authenticated")
+	}
+	// Error message should hint at auth login
+	errMsg := err.Error()
+	if !strings.Contains(errMsg, "auth login") && !strings.Contains(errMsg, "credential") && !strings.Contains(errMsg, "no credential") {
+		t.Errorf("error should mention auth or credential: %v", err)
+	}
+}
+
+func TestCatalogShow_NoAuth(t *testing.T) {
+	withTestHome(t)
+
+	_, err := runCatalog(t, "show", "test-uuid")
+	if err == nil {
+		t.Fatal("expected error when not authenticated")
+	}
+	// Error message should hint at auth
+	errMsg := err.Error()
+	if !strings.Contains(errMsg, "auth login") && !strings.Contains(errMsg, "credential") && !strings.Contains(errMsg, "no credential") {
+		t.Errorf("error should mention auth or credential: %v", err)
+	}
+}
+
+func TestCatalogSearch_RequiresQuery(t *testing.T) {
+	withTestHome(t)
+
+	_, err := runCatalog(t, "search")
+	if err == nil {
+		t.Fatal("expected error when query is missing")
+	}
+	// Should mention that query argument is required
+	errMsg := err.Error()
+	if !strings.Contains(errMsg, "requires") && !strings.Contains(errMsg, "arg") {
+		t.Errorf("error should mention missing argument: %v", err)
+	}
+}
+
+func TestCatalogShow_RequiresUUID(t *testing.T) {
+	withTestHome(t)
+
+	_, err := runCatalog(t, "show")
+	if err == nil {
+		t.Fatal("expected error when UUID is missing")
+	}
+	// Should mention that UUID argument is required
+	errMsg := err.Error()
+	if !strings.Contains(errMsg, "requires") && !strings.Contains(errMsg, "arg") {
+		t.Errorf("error should mention missing argument: %v", err)
+	}
+}