Unencrypted DOH Only Mode

[0x0D15]

Prerequisites

• I have checked the Wiki and Discussions and found no answer

• I have searched other issues and found no duplicates

• I want to request a feature or enhancement and not ask a question

The problem

When using unecrypted DOH (via allow_unencrypted_doh) and disabling plain DNS + other encrypted DNS mechanisms AdguardHome fails to start with disabling plain dns requires at least one encrypted protocol.

Proposed solution

Allow users to use only unecrypted DOH.

Alternatives considered and additional information

No response