AdguardTeam / AdguardTeam/dnsproxy

Bug Report: upstream doh queries use random tls v1.2 or v1.3 for different servers

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Description

dnsproxy v0.82.0, Windows 11
Upstreams: IP-based DoH (no SNI), e.g. https://149.112.112.9/dns-query

Problem:
After observing random fails on accessing DoH servers, I have found out
dnsproxy negotiates TLS 1.2 with certain DoH upstreams despite those servers supporting TLS 1.3.
Setting tls-min-version: 1.3 in config has no effect on outgoing upstream connections.

Key finding:
Using a 3rd party tool, querying the exact same server, negotiates TLS 1.3 successfully. Confirmed via Wireshark on both sides. This rules out the server and points to a difference in how dnsproxy initializes its upstream HTTP client.
Expected behavior
dnsproxy should negotiate TLS 1.3 with upstreams that support it, consistent with dnslookup behavior.

Request:
Please add the ability to determine upstream tls version

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