Closes #359.Closes #360.

Squashed commit of the following:

commit 26af6d91498087ac831c8eb61b1a54a40107a7e1
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Nov 2 15:08:56 2023 +0300

    all: redo basic auth

commit 753fd688ee6d35fb258dd9f9c2fa572c4e07eb75
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Wed Nov 1 18:01:00 2023 +0300

    all: imp docs, names

commit 2c1f47690f58d0dabba40f29ae273d688d6a35f8
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Wed Nov 1 17:27:41 2023 +0300

    all: support basic-auth-only doh mode