Hover and completion on an applied functor show the functor body's types #9072

For a module created by applying a functor, hover and completion show the types of the functor's body instead of the applied signature:

module MakeSet = (O: Ord) => {
  type t = array<O.t>
  let add = (s: t, x: O.t) => s->Array.concat([x])
}
module IntSet = MakeSet({
  type t = int
  let compare = (a: int, b) => a - b
})
let s = IntSet.add([], 1)
//             ^ hover
// let s2 = IntSet.
//                 ^ completion

Hover on IntSet.add shows type IntSet.t = array<O.t>, and completion of IntSet. shows add: (t, O.t) => array<O.t>. The compiler's signature is type t = array<int> and let add: (t, int) => array<int>.

for_module in analysis/src/process_cmt.ml handles Tmod_apply by recursing into the functor's own module expression and ignores the argument.