params_encoded::insert (4 of 5 overloads)

Constructs a key-only query parameter at container position.

iterator
insert(
    iterator before,
    string_view key,
    string_view value);

Iterator to position where the element was constructed

Name	Description
`before`	Position where the new element should be constructed
`key`	Key of the query param
`value`	Value of the query param