libssh-0.12.2

 * Security:
   * CVE-2026-59843: Denial of service via zero advertised channel packet size
     (accidentally missed from previous release backports)
 * Bugfixes:
   * Fix fallback to default provider if FIPS provider does not have ML-KEM
     implementation
   * Do not override explicitly set options through a configuration file to
     match OpenSSH behavior.
   * Return SSH_KNOWN_HOSTS_UNKNOWN when GSSAPI key exchange is used without any
     hostkey
 * New API:
   * API to check the GSSAPI key exchange was used for hostkey handling
   * API to initiate GSSAPI keyex authentication (missing from last release)