useQueryParams: Serialize arrays using brackets and improve typing

Background

This MR has addresses two things:

• In Drupal, queries may expect arrays using bracket notation (c.q. ?foo[]=bar&foo[]=baz&foo[]=qux. When using the queryParams variable to build an URL that bears a search query, array parameters with only one value were cast as strings (i.e. ?foo=bar instead of ?foo[]=bar. This caused bad request errors since Drupal would not expect a string, but an array.
• In TypeScript projects, it was difficult to work with the existing typings since we used the object type, which refers to a Reference Type that may not have a key-value structure. As such, we encountered compilation errors during building.

What's changed

• Ensured that query parameters that receive array values are always serialised using bracket notation (see above)
• Made the JSDoc typings more accurate, which improves TypeScript interop