[5] Account selector, manage accounts and view mode performance on cloud accounts

When using the wallet with a cloud account the top right account selector performs poorly.

You can't access manage accounts drop down, nor does it view the "View Mode" button when browsing an account that doesn't belong the the users cloud account (not in the auth store).

Some performance has to be made to enhance the performance of this and the checks of `isMyAccount` that only triggers when/after a cloud account is logged in (authorized). When wallet times out, the cloud account authorized credentials is no longer available until the next login (authorized).

## Tasks
- [ ] Incorporate solution from #2540
- [ ] Replace all instances of `AccountStore.isMyAccount`
- [ ] Enable Manage Accounts drop-down for cloud accounts
- [ ] Enable "View Mode" for cloud accounts

Start by reading the solution from #2540 and searching the codebase for all instances of AccountStore.isMyAccount. Trace the account selector, Manage Accounts drop-down, and View Mode checks for cloud accounts; done means those controls work for cloud accounts and the checks no longer depend on an authorized login remaining available.

Written by the indexing model from the issue text.