Function import_verifying_key_spki 

pub async fn import_verifying_key_spki(
    variant: EcdsaVariant,
    spki: impl Into<Vec<u8>>,
) -> Result<VerifyingKey, Error>

Import a public key as an X.509 SubjectPublicKeyInfo (DER). The curve must be named by OID and match the declared variant’s, or the import fails Error::InvalidKey; whether a compressed point encoding is accepted is implementation-defined — do not rely on either behavior (see the WIT import-verifying-key-spki doc).