[Cashtab] [wallet mgmt improvements p3] Get all wallet context variables in the same call

Summary:
T2822

Depends on D12842

Artifact here. As additional wallet context variables were needed, they were added in a separate call. Should just be one call.

Test Plan:
Confirm the same variables are being pulled in as before.
npm start
Navigate to settings page
Change active wallet & no issues

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D12843