PR related to the #520 issue

[top-master]

Implements DNS-leak solution mentioned by #520 issue.

Better late than never, however, feel free to remove the AGENTS.md file.

[chipitsine]

vibe coding these days often hallucinate and produce AI slope.
maybe in 5-10 years it will change

[chipitsine]

also, I would keep libhamcore as a module

[top-master]

Nothing in this PR was Vibe-coded, however, I Vibe-merged my changes from another folder into this repo's latest commit. Anyhow, the Github actions and/or workflows seem to pass.

I mean, the only issue I could find was un-related to my changes, and instead says:

'vpnsetup' is not recognized as an internal or external command,
operable program or batch file.

[chipitsine]

what I suggest is to get it properly working in your fork and open a PR once ready

[top-master]

Everything seems to be merged without changing SoftEther's logic, meaning, just like I asked the AI-agent to, only the minimal lines needed for this are merged.

However, the AI-Agent did "improve" a little of my own code, which I reverted in a separate commit. And the detiled comments should prevent future improvements.