feat(dns): expand HTTPS and SVCB inspection output

[ryanfowler]

Summary

• render HTTPS and SVCB records with structured service-binding fields
• preserve and safely display ALPN, ports, address hints, ECH, DoH paths, and unknown parameters
• retain malformed RDATA as bounded, inspectable raw hex and add focused tests

Validation

• gofmt -l .
• go test -v -parallel 8 ./...
• go build .
• staticcheck ./...