UNKNOWN-FAMILY FAIL-CLOSED PROBE — 3d9645200bc5

CONSTRUCTION: two custom seats, same vendor base
http://127.0.0.1:9/v1, same model:
  describe_spec families: ['unknown', 'unknown']
  built seat families:    {'vendor-a': 'unknown', 'vendor-b': 'unknown'}
  -> both seats are family 'unknown': the machinery cannot tell they share a vendor,
     so independence must fail closed. It does, on all three surfaces:

(a) Tech Lead, designated = unknown-family seat
    (raiser/refuter known families):
    chosen = 'knownseat' (family 'famK')
    substitution recorded: "the designated Tech Lead seat's family is unknown — independence cannot be shown"
    designated unknown with raiser/refuter also
    'unknown' (the claim's exact shape):
    chosen = 'knownseat'; substitution reason: "the designated Tech Lead's family raised or refuted this finding — an adjudicator must be independent, so the designation was rejected for this case"
    panel of ONLY unknown seats: chosen = None, unavailable = 'no seat from a family independent of both the raiser and the refuter served on this panel'
    ASSERTION HELD: unknown never adjudicates.

(b) run_review, blocking finding raised by an
    unknown-family seat, second seat also unknown:
    standing findings' cross_family marks: ['unknown_family']
    gate = blocked
    ASSERTION HELD: marked 'unknown_family' — never multi-family, never confirmed away.

(c) verify_record on an all-unknown record:
    two_families ok = False (distinct known families: [])
    ASSERTION HELD: two unknown seats cannot satisfy the two-family independence check.

PROBE OUTCOME: fail-closed on construction, Tech
Lead selection, cross-family treatment, and
record verification. Supports the pre-filled
recommendation: sustain refutation (probe-backed).
