message: Add secp256k1_verify documentation
diff: @@ -30,6 +30,15 @@ const UNCOMPRESSED_PUBKEY_LENGTH: usize = 65;
  /// Max length of a serialized public key
  pub const PUBKEY_MAX_LENGTH: usize = UNCOMPRESSED_PUBKEY_LENGTH;
  +/// ECDSA secp256k1 implementation.
  +///
  +/// This function verifies message hashes (typically, hashed unsing SHA-256) against a signature,
  +/// with the public key of the signer.
  +///
  +/// The signature and public key are in "Cosmos" format:
  +/// - signature: Serialized "compact" signature (64 bytes).
  +/// - public key: [Serialized according to SEC 2](https://www.oreilly.com/library/view/programming-bitcoin/9781492031482/ch04.html)
  +/// (33 or 65 bytes).
  pub fn secp256k1_verify(
  message_hash: &[u8],
  signature: &[u8],
  