add nova

nova/src/Fields/Markdown/DefaultPreset.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Laravel\Nova\Fields\Markdown;
+
+use Illuminate\Support\Str;
+
+class DefaultPreset implements MarkdownPreset
+{
+    /**
+     * Convert the given content from markdown to HTML.
+     *
+     * @param  string  $content
+     * @return string
+     */
+    public function convert(string $content)
+    {
+        return Str::markdown($content);
+    }
+}