Add missing openapi query & response specifications to schemas

[andrew-wang0]

Extension of #79

Currently, many keys in our schemas have no good examples or descriptions.

For example, the below is missing examples

And the below is missing descriptions

Add openapi metadata to all routes with missing examples and descriptions to help users understand the query params and response schemas.

See the LARC endpoint for an example of a fully documented endpoint using openapi.

[rsahyoun]

I can take this task if that works for you.