Be selective about which wallets we show who do not yet support payjoin & what action to take

We might want to target wallets that are open to change rather than any ol' wallet.

We could also change the links on that side to be `mailto:` links that pop up a template asking the dev to check out payjoin.org (and cc us) because the person who clicked would like them to consider what it would take to add payjoin to their stack.