[EPIC] Polish Export UI

[sssoleileraaa]

Description

• Add a close link in the top right-hand corner
• Add a task description and update margins and spacing between the task description, error message, instructions, and button panel, see zeplin
  
  Note: There's actually a Continue button in the client because of how we communicate between the Export and Client VMs. If you have to use placeholder text until Finalize Export messaging and behavior #549 is finished, that is fine. The focus of this Issue is UI styling - fonts and formatting and that sort of thing.

[sssoleileraaa]

Also pay attention to:

• letter-spacing
• font styles
• button outlines
• bg color
• overlay outline

[ninavizz]

Yeah, no more "close" link in upper-right corner. :(( For the Pilot Beta release, anyway.

Zeplin Draft, from 24 Nov meeting to agree on messaging and basic flow.

Text may be copy/pasted from draft. Because there is not a specific GH Issue for content, alone, I will keep the canonical source-of-truth in copyediting for these windows, in Zeplin.

Also, see This UX Repo Issue as canonical source-of-truth for allthings Export.

[eloquence]

(We're tackling this incrementally, so tagging as epic and tracking in near-term backlog until all components are complete.)

[eloquence]

(This issue is quite dated and no longer useful as an organizing epic; we can track iterative improvements without an epic. Closing.)