Note box on View Metadata modal has usability bugs

Problems

The Notes box on the View Metadata modal has some issues:

• The field is not a rich-text field but is treated as HTML
• The save button does not work in the typesetting workflow, and may not work in some other workflows, because the JS function submit_note is not defined.
• The icon or image that goes with each note is missing from the CDN, or the CDN is down
• The output is not marked as safe when displayed
• The delete button does not work--it results in a server error

Proposed solutions

Display the notes on View Metadata, but remove the submit and delete buttons. Move the interactive parts of this feature out of the modal, into a separate Edit page (maybe Edit notes), like we do with Edit metadata and Edit author metadata. Update the views and the form logic so that all the interaction works without JS. Remove the old JS.

Alternatives

Keep the functionality in the View Metadata pane, but rewrite the JS in ES6 and make sure it works across pages that have access to View Metadata.

Start with the View Metadata modal, its views and form logic, and trace the undefined submit_note path in the typesetting workflow. Compare the existing Edit metadata and Edit author metadata flows before separating note editing into an Edit notes page. Done means notes display correctly while submit and delete work without modal JavaScript or server errors, with the old JS removed.