Create a new, random, unestablished ECIES session.
This method will use the
MATRIX_QR_CODE_LOGIN
info for domain separation when creating the session.
Create a [EstablishedEcies] from an initial message encrypted by the
other side.
Create an [EstablishedEcies] session using the other side's Curve25519
public key and an initial plaintext.
After the channel has been established, we can encrypt messages to send to the other side. The other side uses the initial message to establishes the same channel on its side.
Get our [Curve25519PublicKey].
This public key needs to be sent to the other side to be able to establish an ECIES channel.
An unestablished ECIES session.