BA-1131- Implement design changes to CWU proposal

[kvangorp]

feat(proposals): Implement design changes to CWU proposal

• If a user started or submitted a proposal for an opportunity that is now closed, add a banner with a link to allow them to view (but not edit) the proposal
• Enable users to download their uploaded attachments
• Save a proposal as a draft when the modal is closed, and remove all other 'Save' buttons from the modal

Do not merge upon approving this PR as additional changes may be needed

Fixes BA-1131 (BA-1158, BA-1159, BA-1160)

[sutherlanda]

@mark-a-wilson is this okay to merge? Are you still working on the UI?

[mark-a-wilson]

It's been a while since I've checked, but I think I finished all the UI fiddling I wanted to do. It's going to break the the functional tests, anyway though, isn't it?

[sutherlanda]

Functional tests are not currently functional anyway. I can merge this to dev

[mark-a-wilson]

😂