XLM wallet UI - public memo and private note fields are easily muddled

The UI makes it easy mix the public memo and encrypted note fields. Memo ID's are often required for payments to be authorized or correct online accounts credited. A missing memo can at best require manual intervention to resolve and loss of funds at worst. Alternately notes which where intended to be encrypted in a private keybase wallet could be irreversibly be published to the the global ledger.

I think the private notes should not be added on the same screen as the public memo.

Start at the XLM wallet UI entry point and trace where the public memo and encrypted private note fields are presented. Define the separate-screen behavior and verify that public memos remain available for payment authorization while private notes are not exposed to the global ledger.

Written by the indexing model from the issue text.