Feature request: ignore $schema node

[ericnewton76]

Json schema standard allows for a "$schema" property added to the root object of a json document. Many IDEs like VSCode can enforce schema/describe properties for the user.

I propose adding a special case for json-server to ignore the initial "$schema" : "./myapi-schema.json" node

So FYI a db.json file would look like:

{
  "$schema": "./db-schema.json",
  "posts": [],
  "comments": []
}

This could eventually morph into support for emitting 405 Bad Request for incoming data that doesnt match schema but thats not in scope for this particular effort.

[ericnewton76]

IF I were to add a pull request, tbh I dont know how I'd test it beyond "doesnt error with $schema node"