@type t() :: %SignCore.CMS.Parsed{
  certificates: [SignCore.X509.t()],
  content_oid: tuple(),
  der: binary(),
  digest_algorithm: digest_algorithm() | {:unknown_oid, tuple()},
  leaf: SignCore.X509.t(),
  message_digest: binary(),
  signature: binary(),
  signature_algorithm: signature_algorithm() | {:unknown_oid, tuple()},
  signed_attrs: [tuple()],
  signing_time: DateTime.t() | nil,
  to_be_signed: binary()
}

Fields:

• :der — the original ContentInfo DER (binary).
• :signed_attrs — raw Attribute tuples as the OTP codec emits them. Useful for callers that want to inspect non-required attributes.
• :to_be_signed — DER of signedAttrs re-encoded under the universal SET OF Attribute tag. This is the input the signer committed to; verifiers feed it to :public_key.verify/4 (or Pkcs11ex.verify_bytes/3).
• :signature — raw signature bytes lifted from SignerInfo.signature.
• :digest_algorithm / :signature_algorithm — atom shorthands for the algorithm OIDs found inside SignerInfo.
• :leaf — the leaf signing certificate as a parsed SignCore.X509. This is the cert whose IssuerAndSerialNumber matches the SignerInfo.sid.
• :certificates — the full embedded chain (leaf first), every entry parsed.
• :content_oid — the eContentType OID from EncapsulatedContentInfo. For PAdES B-B this should be id-data.
• :message_digest — the bytes carried in the messageDigest signed attribute. Verify must compare this to the freshly computed digest of the document.
• :signing_time — DateTime.t() lifted from the signingTime attribute, or nil if absent. Informational only — the bytes were committed to but the signer chose them; trustworthy time-binding lives in RFC 3161 timestamps (Phase 5).