Merge in GO/dnsproxy from 324-refactor-upstream to master

Closes #324.

Squashed commit of the following:

commit cceed0b0d49988db3bb58f3c64ca26e5a7ef03b7
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 18 15:48:15 2023 +0300

    proxy: fix check

commit 3b0a231436afc51fa1a5baa2dcb3613517348dc2
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 18 13:55:34 2023 +0300

    all: imp tests again

commit eba1be66
Merge: c4e73af9 5864a879
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Apr 17 19:20:29 2023 +0300

    Merge branch 'master' into 324-refactor-upstream

commit c4e73af9
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Apr 17 15:00:58 2023 +0300

    upstream: fix tests

commit 1bc8d368
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Apr 17 14:46:16 2023 +0300

    all: imp code, docs

commit c9ec31f7
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 14 19:48:33 2023 +0300

    upstream: imp logging, field alignment

commit 418df4c9
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 14 19:08:15 2023 +0300

    upstream: imp code

commit 92df4534
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 14 18:45:54 2023 +0300

    upstream: bootstrap plain dns

commit 44c9e386
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 14 14:07:10 2023 +0300

    upstream: fix tests, imp docs

commit 4c0959d3
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 14 12:30:00 2023 +0300

    upstream: imp code, docs

commit 33819170
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Wed Apr 12 21:27:55 2023 +0300

    upstream: refactor doq

commit 0bd11e10
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Wed Apr 12 21:01:30 2023 +0300

    upstream: refactor doh

commit 29ce52f7
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 11 19:34:37 2023 +0300

    all: refactor dot

commit 6c9d87e9
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 11 01:34:41 2023 +0300

    upstream: refactor dnscrypt, imp code

commit f1117298
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 11 19:53:16 2023 +0300

    all: imp code, docs

commit 726d9377
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon Apr 10 17:06:35 2023 +0300

    all: imp code, add tests

commit 550f1ab5
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 7 19:42:20 2023 +0300

    all: imp docs

commit 66986633
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Fri Apr 7 19:28:54 2023 +0300

    all: introduce bootstrap pkg