The packet-auth-policy change extends the DecodeState enum with DECODE_OPAQUE
and DECODE_POLICY_REJECT. test_E1_perhaps_decode_fuzz drives arbitrary
ciphertext through perhapsDecode and asserted the verdict was one of the
original three states; random ciphertext that matches no channel with no PKI
attempt now returns DECODE_OPAQUE, tripping the assertion. Broaden the check to
accept all five valid verdicts, matching the test's stated 'any verdict is
fine' contract.