Enable DoH/DoT for Private Resources

[samumatic]

Summary

Add support for DNS over HTTPS (DoH) and DNS over TLS (DoT) for Pangolin HTTPS Private Resources, so users can keep system-level Private DNS enabled while accessing Pangolin-managed private resources.

Motivation

Many users run system-wide Private DNS (for example with Control D or NextDNS). Currently, Pangolin’s DNS override does not work well in this setup, forcing users to disable Private DNS to access Pangolin resources.

Supporting DoH/DoT would allow Pangolin to work alongside modern encrypted DNS setups without requiring users to turn them off.

This could be related to the Discussion Dns issues #2377.

Proposed Solution

I would like to see this feature to be Private DNS independent, users using Private DNS should have the same user experience as users using Public DNS resolvers. Resources should not be "Public DNS Only" or "Private DNS Only".

Alternatives Considered

No response

Additional Context

No response