[klippy]

It's because md5 is not an encryption algorithm, it's a hashing algorithm, that's why there's no decoding (it's not just AMXX, any other language). Also md5 hasn't been considered cryptographically secure for a long time, so your effort (mostly) doesn't even matter.
Such data like ammo packs is not secure/secret data so it doesn't matter. Why and how would anyone change values in your sqlite database?