AND-3 Fix visually increasing the balance after sending CCD

[Radiokot]

Purpose

_Describe the purpose of the pull request, link to issue describing the problem, etc.

Changes

• Fix processing transfers as unshieldings
• Remove unused Transaction methods

Checklist

• [x] My code follows the style of this project.
• [x] The code compiles without warnings.
• [x] I have performed a self-review of the changes.
• [x] I have documented my code, in particular the intent of the hard-to-understand areas.
• [x] (If necessary) I have updated the CHANGELOG.