Return string instead of string[] in single mode for Select component

[lu-perfect]

We noticed a potential inconvenience with the Select component behavior: it always returns a string[], even when it's used in single mode.

This design can feel unintuitive and lead to extra boilerplate for developers who just need a single string value when working with the single mode.

If this improvement resonates with you or causes frustration in your daily work, please like/react to this issue so we can gauge how important it is to our community! 👍