Function end_rmac_session 

pub fn end_rmac_session(end_session: bool) -> Capdu

Build an END R-MAC SESSION (CLA 80, INS 78) plaintext C-APDU. end_session selects P2 0x03 (end and return the R-MAC) vs 0x01 (return only). The response returns the 8-byte R-MAC, so Le = 00 is present.