Updates AdguardTeam/AdGuardHome#4695.
Updates AdguardTeam/AdGuardHome#5190.

Squashed commit of the following:

commit 535edd8a496c74f3fb5e98b3debb684ebfc70820
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Dec 1 18:23:15 2022 +0300

    proxy: use mutexes better

commit fe301f47c67a2b9e31b7653b9acac9647dcad568
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Thu Dec 1 18:11:59 2022 +0300

    proxy: add cache clear api