Note to share recipient should be included in email

**Is your feature request related to a problem? Please describe.**
When leaving a note to a recipient in a link share, the note is not very obvious and requires the user to see and click the tiny speech bubble in the top bar even though their attention will be drawn to the content.

Additionally, when sharing by email the email is sent before a note can be made. A user might expect the note to be part of the email.

**Describe the solution you'd like**
I would like the note to recipient to be displayed as a modal dialogue that the user can read and dismiss every time the link is opened. The dismissal should be based on a session cookie as the link may be shared with different people.

I would also like to be able to set a note before sending an email share and have it included in both the email and the page when opened (but perhaps already dismissed).

**Describe alternatives you've considered**
Making the note appear as a permanent message somewhere prominent rather than a modal that is dismissible. This would be fine for small content, but if a lengthy or formatted message is set it might not be appropriate.