feat: add asciidoc editor module (#5954)

* feat: add asciidoc editor module

* fix storage file extension for asciidoc pages

* fix: asciidoc editor + rendering improvements

* fix: description list css improvements

Co-authored-by: NGPixel <github@ngpixel.com>

server/modules/rendering/asciidoc-core/renderer.js

@@ -0,0 +1,26 @@
+const asciidoctor = require('asciidoctor')()
+const cheerio = require('cheerio')
+
+module.exports = {
+  async render() {
+    const html = asciidoctor.convert(this.input, {
+      standalone: false,
+      safe: this.config.safeMode,
+      attributes: {
+        showtitle: true,
+        icons: 'font'
+      }
+    })
+
+    const $ = cheerio.load(html, {
+      decodeEntities: true
+    })
+
+    $('pre.highlight > code.language-diagram').each((i, elm) => {
+      const diagramContent = Buffer.from($(elm).html(), 'base64').toString()
+      $(elm).parent().replaceWith(`<pre class="diagram">${diagramContent}</div>`)
+    })
+
+    return $.html()
+  }
+}