Support DISCLOSURE_LIST form field

[Kadrian]

This adds support for a new field with type DISCLOSURE_LIST. It's a collapsible / expandable section of nested fields, which are all always sent to the sever (in contrast to TABS, where only the active tab is sent), and it's a "creatable" list, meaning the DISCLOSURE_LIST field can be used for a single disclosure section, but it allows adding additional disclosure sections by clicking a plus button. The value sent to the backend is always an array of disclosures

Array<{ [fieldname: string]: unknown }>

Also, this

• extracts the form fields into individual components
• adds tailwind css to slowly move towards a less verbose way of styling