Feature Request: Allow Markdown Syntax for before_input and after_input

[samtrion]

For better formatting of the fields, using Markdown syntax for the field properties before_value and after_value would be advantageous. This would enable providing additional information with a link or emphasizing keywords.

- label: Draft State
  name: draft
  widget: boolean
  default: true
  i18n: duplicate
  after_input: If enabled, the page is not ***published***.
  preview: false