feat: match objects support JSON Schema

[AndersDJohnson]

Match objects could support optionally using a JSON Schema compatible structure to validate some objects or nested objects. This would enable a declarative alternative to functions, which don't work in static files like JSON, e.g., for record groups in config (#401).

We could use a $schema meta property to indicate dropping into a JSON Schema. We would want to provide a way to override the $ prefix on $schema to support handling any namespace conflicts.

For example, the below would require the query params firstName, lastName, and ensure one called favoriteColor matches one of the values in the specified enumeration. We could mix with existing features, as in this example, where someParam must also be present with a value of "someValue".

mockyeah.get({
  query: {
    someParam: "someValue",
    $schema: {
      favoriteColor: {
        type: "array",
        items: {
          type: "string",
          enum: ["red", "blue", "yellow"]
        }
      },
      required: ["firstName", "lastName"]
    }
  }
})