Allow hiding "Total balance" in the sidebar

[kdembler]

Currently "Total balance" is always displayed in the sidebar with the sum of all the tokens belonging to all your accounts. For privacy reasons when being in public or screensharing, I think we should add an option of hiding that balance, for example like Subwallet allows:

https://github.com/Joystream/pioneer/assets/12646744/80d30fa3-475e-41ef-b3fe-27d6f757ed33

[dmtrjsg]

We discussed this before and thought it could be easily achieved by just hiding the wallets from the extensions.

but hiding it in the app would be a nice enhancement to it..

[kdembler]

Let's try adding a little eye icon here that would work the same way as in video I posted above. The setting should be persisted between sessions