[Cashtab] Re-implement 11008 after UI landing

Summary:
See D10970 and D11008

Changes from D11008 were reverted inadvertently in D10970. This diff brings them back in.

Test Plan:
npm test and ensure all pass
Review D10970 to confirm no other non-design-related changes

Reviewers: emack, #bitcoin_abc, johnkuney

Reviewed By: #bitcoin_abc, johnkuney

Differential Revision: https://reviews.bitcoinabc.org/D11064