[feature] track the token statistic response of the used provider services used in a session/project.

[andkoma]

To be able to react on the different pricing, quality, speed and limitations of the services and contract models used:

• a first step would be to optional track the provided response information during a session for each request, maybe also in a database for evaluation for a specific project. ( TOKEN_TRACKER_ACTIVE = True )
• in further steps this could influence which service could or should be used in which order ( load balancer, fallback handler, cost/speed/quality optimizer ).