Returns all assertions in this metadata.
StaticfromMetadata with the given [predicate, object] assertions.
Adds an assertion to the metadata.
The predicate for the assertion (accepts KnownValue, string, etc.)
The object for the assertion
A new SignatureMetadata with the assertion added
Returns whether this metadata contains any assertions.
Metadata associated with a signature in a Gordian Envelope.
SignatureMetadataprovides a way to attach additional information to signatures, such as the signer's identity, the signing date, or the purpose of the signature. When used with the signature extension, this metadata is included in a structured way that is also signed, ensuring the metadata cannot be tampered with without invalidating the signature.