Improve E2EE UI in desktop app (github: #6458)

I have been working on this Issue.

I just wanted to confirm if the "Enable Encryption" checkbox in the attached screenshot is required in SyncWizard.
Also wanted to confirm that, after clicking checkbox should it behave same as "Enable Encryption" button in Encryption window of settings?

Is my approach right?

Looks ok to me, if I understand the requirements correctly. I don't use encryption so have no first-hand experience setting it up.