In transaction list, show different icon when receiving from taddr vs zaddr

[leto]

Receiving a t=>z versus a z=>z makes a difference for metadata leakage reasons and currently the user can't tell at all except by going to the explorer, which leaks more metadata and could be wrong

[leto]

we could use an open lock for transactions involving any taddrs, a closed lock for xtns that have at least one zaddr and a green lock for pure z2z xtns

[oDinZu]

Should we work on this since we are going Z to Z?

[leto]

@csharpee t=>z tx's will stil be allowed when we are z2z, but not z=>t tx's