Add persisted version of showConnect

[janniks]

Right now showConnect doesn't persist selection (for backwards comp)

But users might want this, so we should have a showConnectPersist, which stores the provider id.

This could be changed to a breaking change to always persist showConnect later.

[kyranjamie]

This would be a great addition, especially as we move away from shared namespaces.

[markmhendrickson]

Might it even be better to have showConnect be the persisted version, since presumably this is what developers expect / the need for not persisting is less common?

[kyranjamie]

This is important as once apps have authenticated, another wallet provide may be called erroneously, owing to how they complete for the shared namespace.

[janniks]

+1 sort of agree here
But will be breaking, as to get the old behavior, folks would need to call disconnect each time. (Which they may not know about). But seems like a good change 👍🏻