Parse TLS details (version, cipher, bits, cert verification) from the
Postfix Received header parenthetical and expose them per hop, rendered
as a per-hop badge in the Email Path card.
Add an x-tls Authentication-Results result: parse it when present, and
otherwise synthesize it from the inbound hop's TLS info. A negative
result (unencrypted inbound connection) applies a -10 authentication
score penalty and is shown in the Authentication card. Enable the TLS
handler in authentication_milter.
Closes: #40
Compare the HELO/EHLO hostname announced by the sending server (first
Received hop) against the sender IP's PTR records, surfacing the same
signal as x-ptr/policy.ptr in Authentication-Results. Adds helo_hostname
and helo_ptr_match to DNSResults, applies a 15-point PTR sub-score
penalty on mismatch, and displays the result in a new HELO/PTR
Consistency card.
Explains the two most common causes: the mail server not being
configured to verify email authentication, or a receiver hostname
mismatch with --receiver-hostname.
Bug: https://github.com/happyDomain/happydeliver/issues/11
