Relates to: #124

This attempts to determine if there was a cache hit and then records that along with cache key, operation name and path attributes.

By default, this calls cache_lookup_event() which has no action.

Implementing the gem in the parent application would enable monitoring (or whatever) of these cache hits. In our case, we probably just want to increment a cache hit or miss metric tagged with the path and operation name.

module GraphQL
  module FragmentCache
    class Fragment
      def self.cache_lookup_event(**args)
        # Monitoring such as incrementing cache hit counter
      end
    end
  end
end