make Qr Payload
Build v2 QR transport payload: SD-JWT combined presentation: issuerJWS~disc1~...~discN~kbJWS?
=> JSON { vc1, vc2, vc3 } -> UTF8 -> zlib -> base64url
vc1 = issuer JWS header (b64url) vc2 = issuer JWS payload decoded as UTF-8 JSON string vc3 = issuer JWS signature (b64url) + "~" + disclosures + "~" + kbJWS?