feat: enable enterprise users to specify a custom logo (#5566)

* feat: enable enterprise users to specify a custom logo

This adds a field in deployment settings that allows users to specify
the URL to a custom logo that will display in the dashboard.

This also groups service banner into a new appearance settings page.
It adds a Fieldset component to allow for modular fields moving forward.

* Fix tests

enterprise/coderd/appearance_test.go

@@ -0,0 +1,66 @@
+package coderd_test
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/coder/coder/coderd/coderdtest"
+	"github.com/coder/coder/codersdk"
+	"github.com/coder/coder/enterprise/coderd/coderdenttest"
+	"github.com/coder/coder/testutil"
+)
+
+func TestServiceBanners(t *testing.T) {
+	t.Parallel()
+
+	ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+	defer cancel()
+
+	adminClient := coderdenttest.New(t, &coderdenttest.Options{})
+
+	adminUser := coderdtest.CreateFirstUser(t, adminClient)
+
+	// Even without a license, the banner should return as disabled.
+	sb, err := adminClient.Appearance(ctx)
+	require.NoError(t, err)
+	require.False(t, sb.ServiceBanner.Enabled)
+
+	coderdenttest.AddLicense(t, adminClient, coderdenttest.LicenseOptions{
+		ServiceBanners: true,
+	})
+
+	// Default state
+	sb, err = adminClient.Appearance(ctx)
+	require.NoError(t, err)
+	require.False(t, sb.ServiceBanner.Enabled)
+
+	basicUserClient := coderdtest.CreateAnotherUser(t, adminClient, adminUser.OrganizationID)
+
+	// Regular user should be unable to set the banner
+	sb.ServiceBanner.Enabled = true
+	err = basicUserClient.UpdateAppearance(ctx, sb)
+	require.Error(t, err)
+	var sdkError *codersdk.Error
+	require.True(t, errors.As(err, &sdkError))
+	require.Equal(t, http.StatusForbidden, sdkError.StatusCode())
+
+	// But an admin can
+	wantBanner := sb
+	wantBanner.ServiceBanner.Enabled = true
+	wantBanner.ServiceBanner.Message = "Hey"
+	wantBanner.ServiceBanner.BackgroundColor = "#00FF00"
+	err = adminClient.UpdateAppearance(ctx, wantBanner)
+	require.NoError(t, err)
+	gotBanner, err := adminClient.Appearance(ctx)
+	require.NoError(t, err)
+	require.Equal(t, wantBanner, gotBanner)
+
+	// But even an admin can't give a bad color
+	wantBanner.ServiceBanner.BackgroundColor = "#bad color"
+	err = adminClient.UpdateAppearance(ctx, wantBanner)
+	require.Error(t, err)
+}