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>

client/components/editor/markdown/fold.js

@@ -1,62 +0,0 @@
-// Header matching code by CodeMirror, copyright (c) by Marijn Haverbeke and others
-// Distributed under an MIT license: https://codemirror.net/LICENSE
-
-import CodeMirror from 'codemirror'
-
-const maxDepth = 100
-const codeBlockStartMatch = /^`{3}[a-zA-Z0-9]+$/
-const codeBlockEndMatch = /^`{3}$/
-
-CodeMirror.registerHelper('fold', 'markdown', function (cm, start) {
-  const firstLine = cm.getLine(start.line)
-  const lastLineNo = cm.lastLine()
-  let end
-
-  function isHeader(lineNo) {
-    const tokentype = cm.getTokenTypeAt(CodeMirror.Pos(lineNo, 0))
-    return tokentype && /\bheader\b/.test(tokentype)
-  }
-
-  function headerLevel(lineNo, line, nextLine) {
-    let match = line && line.match(/^#+/)
-    if (match && isHeader(lineNo)) return match[0].length
-    match = nextLine && nextLine.match(/^[=-]+\s*$/)
-    if (match && isHeader(lineNo + 1)) return nextLine[0] === '=' ? 1 : 2
-    return maxDepth
-  }
-
-  // -> CODE BLOCK
-
-  if (codeBlockStartMatch.test(cm.getLine(start.line))) {
-    end = start.line
-    let nextNextLine = cm.getLine(end + 1)
-    while (end < lastLineNo) {
-      if (codeBlockEndMatch.test(nextNextLine)) {
-        end++
-        break
-      }
-      end++
-      nextNextLine = cm.getLine(end + 1)
-    }
-  } else {
-    // -> HEADER
-
-    let nextLine = cm.getLine(start.line + 1)
-    const level = headerLevel(start.line, firstLine, nextLine)
-    if (level === maxDepth) return undefined
-
-    end = start.line
-    let nextNextLine = cm.getLine(end + 2)
-    while (end < lastLineNo) {
-      if (headerLevel(end + 1, nextLine, nextNextLine) <= level) break
-      ++end
-      nextLine = nextNextLine
-      nextNextLine = cm.getLine(end + 2)
-    }
-  }
-
-  return {
-    from: CodeMirror.Pos(start.line, firstLine.length),
-    to: CodeMirror.Pos(end, cm.getLine(end).length)
-  }
-})