Filter Transform Documentation

[shellscape]

There's a lot of room for improvement of the filter documentation. (And because I don't have an intimate knowledge of how that transform works, I cannot suggest improvements in PRs at this time). For example, if I have this filter configuration:

- filterSchema:
  - Query.{getAssociates}

Mesh will successfully provide only the getAssociates query. However, if I add:

- filterSchema:
  - Query.{getAssociates}
  - Associate

with the intent of using on the getAssociates query and only adding the Associate type to the schema, Mesh goes awry and produces a schema with type Query with no child fields, and lacking the Associates type, but including all other types.

It would be grand if Mesh were able to figure out which types were needed based on the GraphQL AST, but at the least I'd like to be able to specify which types to take, leaving out all others. As it is, the documentation doesn't mention that, nor does it mention using wildcards to remove all fields of a type.

[gilgardosh]

Seems like the filter schema doc has been significantly expanded since this issue opened
https://the-guild.dev/graphql/mesh/docs/transforms/filter-schema