Add XChaCha20/XChaCha20-Poly1305/cascaded algorithm, using a 64-bit counter to support large files.

[fzxx]

• The key derivation method is consistent with AES-256.
• The registry records the XChaCha20/XChaCha20-Poly1305 option.
• Use a 64-bit counter to support very large files.
• Add cascaded key derivation, cascaded encryption algorithm.

# AES-256
7z a archive.7z -ppassword -mhe=on
7z a archive.7z -ppassword -mhe=on -mem=aes256
7z a archive.7z -ppassword -mhe=on -mem=aes-256

# XChaCha20
7z a archive.7z -ppassword -mhe=on -mem=xchacha20

# XChaCha20-Poly1305
7z a archive.7z -ppassword -mhe=on -mem=xchacha20poly1305
7z a archive.7z -ppassword -mhe=on -mem=xchacha20-poly1305

# AES+XChaCha20-Poly1305
7z a archive.7z -ppassword -mhe=on -mem=axp
7z a archive.7z -ppassword -mhe=on -mem=aesxchacha20poly1305
7z a archive.7z -ppassword -mhe=on -mem=aes+xchacha20-poly1305

# AES+XChaCha20+Ascon
7z a archive.7z -ppassword -mhe=on -mem=axa
7z a archive.7z -ppassword -mhe=on -mem=aesxchacha20ascon
7z a archive.7z -ppassword -mhe=on -mem=aes+xchacha20+ascon

[fzxx]

I noticed that the 7z password derivation does not use a random salt. This is a security issue, and I wonder why. If it's because of speed, I suggest using the standard PBKDF2, which also makes it easy to add a salt. If anyone has a need for MAC, I can also add XChaCha20-Poly1305. @ip7z

[fzxx]

Add XChaCha20-Poly1305. Feature fully implemented. If this PR/branch doesn't get merged, I will start a separate project for everyone to use.