v1.7.0

RFC 9989 evidence-first ladder. DMARCbis (RFC 9989/9990/9991, May 2026) deprecates the pct tag, so the stepped pct=25 rung is gone: the DMARC ladder is now none -> quarantine -> reject, with no pct ever emitted and the deprecated pct/rf/ri tags stripped from every generated record. Scan-derived recommendations cap at p=quarantine (alignment-gated); p=reject is recommended only by the aggregate-report readiness engine. The validator warns on deprecated tags and explains the new t=y test-mode tag; an enforcing policy carrying t=y is reported as test mode, not enforcement. Tool count unchanged at 16.