It's not a "real-life issue" since SQLiteCpp can only bind a blob with a size in int.
I created a PR nonetheless, but I'll take the time to think about it twice; it might be better in fact to NOT try to hide that API and let the developer know

I am currently using this great library. Thank you for this!

One issue I'm running into is binding a blob breaks the variadic binding possiblity, because it requires two parameters, not one.

So I would like to introduce a new struct Blob or similar, that wraps a void pointer and std::size_t, so I can use it in a variadic binding suitation, e.g.:

// [...]
struct Blob {
    const void *ptr;
    std::size_t size;
};
SQLite::bind(st, "ABC", 2, SQLite::Blob{"def", 3});

I think this would perfectly fit in this PR, what do you think?