Wrap `[u8; WORD_LENGTH]` under a `struct Word([u8; WORD_LENGTH])` in order to `impl Display for Word` if you really want a base 64 display?

Maybe wrap `[u8; WORD_LENGTH]` under a `struct Word([u8; WORD_LENGTH])` in order to `impl Display for Word` if you really want a base 64 display?

_Originally posted by @tbrezot in https://github.com/Cosmian/findex-server/pull/90#discussion_r2190702181_
            