add auth/checks to nonprofit posting endpoints

[jd2rogers2]

requirements a little loose here as we'll need to assess what's needed when we get to this point
but in general endpoints for acting on behalf of a nonprofit need to check if the current user has the right permissions

This will require adding a roles guard in the AuthModule (guard is a functionality provided by NestJs).

Inside the guard you will have to read the User-Orgs table. Each org will have a user that can be an agent. The guard logic is a pseudo code like:

This guard requires a user to be in the request
find userorg record for current user
if no userord record return false
if userOrg record for current user make sure that the org in question is in the same user-org record (there could be multiple records)

To get the authenticated user from the request, you may want to add a Cookie Guard annotation before the new guard annotation so that the Cookie guard puts the user in the middleware.

preReq #59