SANSOFT Verifier V1.2.4 — decision stabilise
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Three outputs: kept.csv / review.csv / dropped.csv (status + reason + MX + Website).

Decision rules (honest):
- keep_high only when real MX + website available
- a_only (resolves, no MX) → review (not "MX and website")
- null MX (RFC 7505) → dropped
- role without real MX → review
- website restricted (403/401/429) or redirected → review (not dead)
- disposable / edu / gov still drop when those filters are on

Settings "Skip disposable" and "Strict junk TLDs" are applied in pre-check.
CSV headers are written once (no duplicate header rows on re-run).

Not claimed: mailbox verification / guaranteed delivery.
