Support post quantum algorithms

Post quantum algorithms are increasingly being used and implemented (Kubernetes, OpenSSL,...).

In particular, TLS supports post-quantum key exchange via X25519MLKEM768.

This project uses Go 1.24 crypto/tls (which does support this algorithm) but it overrides the curve preferences in such a way that this new algorithms is not selected: https://github.com/dreitier/backmon/blob/7dea0af22149134c3651cb79ec1c3b96501eb654/web/server.go#L32

Removing or adapting this constraint and verifying that the specific patch version indeed supports this algorithm should be enough.

Start at web/server.go line 32, where the TLS curve preferences are overridden, and check how Go 1.24 crypto/tls handles X25519MLKEM768. Remove or adapt that constraint, then verify that the specific Go patch version supports the algorithm and that TLS can select it.

Written by the indexing model from the issue text.