Clean up client/src/models/results

[Stephen-ONeil]

• break up results.js, it's a big jumble of utils, configuration, and classes
  • start porting to TS in the process
• Result and Indicator need to be ironed out a fair bit. They look subject-like, but they are definitely not subjects post-TS subject entities #1169.They should probably be their own thing.
  • maybe just some basic classes with utility methods and separate stores?
  • maybe standalone utility methods and direct GQL queries?
    • there's a lot of places where the current populate_results code makes small efficiencies by cross populating one store with the result's of another's queries. Weigh if it's worth the extra abstractions over just using the apollo cache, or see if it's worth trying to manually populate the apollo cache the same way the stores currently cross-populate