Support for deep-sorting

[Andy2003]

Given the Schema:

type Movie {
  title: String
  publishedBy: Publisher @relation(name: "PUBLISHED_BY", direction: OUT)
}

type Publisher {
  name: ID!
}

The augmentation would be:

type Query {
  movie(sort: [_MovieSorting!]): [Movie!]!
}
enum SortDirection{
  asc,
  desc,
}

input _MovieSorting {
  title: SortDirection
  publishedBy: [_PublisherSorting!]
}

input _PublisherSorting {
  name: SortDirection
}

So a user can get all movies ordered by Publisher.name and title by calling

query {
  movie(sort: [{publishedBy: [{name: desc}]}, {title: asc}]) {
    title
  }
}

which results in this query

MATCH (m:Movie)
WITH m
  ORDER BY head([(m)-[:PUBLISHED_BY]->(p:Publisher) | p.name]) DESC, m.name ASC
RETURN m{.title}

This sorting should be possible for all 1..1 relations.
This is related to #3 since the input of sorting will no longer be an enum.

[jexp]

Break it up into 2 steps

1. input type for sorting
2. optionally deep sorting

question: how do we manage the backwards compatibility if any.

[Andy2003]

we can generate 2 arguments:

1. deprecated enum
2. new input field

[jexp]

Would need to align with neo4j-graphql-js

perhaps we can call the new field: sortBy or sort

/cc @johnymontana

[Andy2003]

Break it up into 2 steps

1. input type for sorting
2. optionally deep sorting

for 1. I created issue #196