update kirby to v5 and add refresh cache panel view button

public/kirby/config/routes.php

@@ -3,9 +3,9 @@
 use Kirby\Cms\App;
 use Kirby\Cms\LanguageRoutes;
 use Kirby\Cms\Media;
-use Kirby\Cms\PluginAssets;
 use Kirby\Panel\Panel;
 use Kirby\Panel\Plugins;
+use Kirby\Plugin\Assets;
 use Kirby\Toolkit\Str;
 use Kirby\Uuid\Uuid;
 
@@ -71,7 +71,7 @@ return function (App $kirby) {
 				string $hash,
 				string $path
 			) {
-				return PluginAssets::resolve(
+				return Assets::resolve(
 					$provider . '/' . $pluginName,
 					$hash,
 					$path