Move files around, formatter helper

Formatters for username belong to account, not to note
New helper for transforming a markdown text to html

frontend-reactive/app/helpers/formatter.ts

@@ -0,0 +1,24 @@
+import { helper } from '@ember/component/helper'
+
+class Token {
+  declare token: string
+  declare elements: Array<string | Token>
+
+  public constructor(token: string) {
+    this.token = token
+    this.elements = new Array()
+  }
+}
+
+export default helper(function formatter(
+  positional: Array<string>,
+  named: {
+    matchers: Array<{ match: RegExp; replace: string }>
+  },
+): string {
+  let out = positional[0] ?? ''
+  named.matchers.forEach((x) => {
+    out = out.replaceAll(x.match, x.replace)
+  })
+  return out
+})