feat: ESM bundling (or export functions in separate files)

[sesam]

would you consider a smaller PR that adds ESM bundling and/or exports all functions in separate files to allow cherry picking imports?

@timhwang21 see #81 - maybe source is still too small to make bundling a reasonably important issue. Or maybe you meant about dependencies? By only importing, say, the encoding part, you would be able to skip all the generator-related stuff.

[timhwang21]

@sesam my main concern was wordlists which makes up the bulk of the bundle. Your other issue captures my concern 😄