chore: indicate compatibility with new v4 major

[danielroe]

Description

With Nuxt 4 on the horizon, this updates the module compatibility definition to allow it to be installed on Nuxt v4. (Otherwise Nuxt will indicate the module might not be compatible.)

When Nuxt v4 comes out then you might decide or need to make breaking changes in this module and release a new major, but hopefully the migration should be smoother. 🙏

👉 You can follow this and other changes in nuxt/nuxt#27613 - please feel free to provide feedback as well!

Linked Issues

Additional context

[prazdevs]

Thanks for the heads up, I eventually plan on making a new major and cleanup stuff when I get some time. Would also be interesting to handle edge cases and use outside of the Vue instances (middleware).
Will keep an eye on v4 🫡