[Feature] Add price of a given question/response pair alongside number of tokens.

[adamzenith]

Problem Description
Currently the tokens can be listed below each query, but this does not reflect how much you will be billed by the API as different providers/models have different prices.

Proposed Solution
The model providers have their $/1k tokens listed on their api pricing pages. This could be used to calculate how much each query costs.

[Barafu]

If you do this, please keep in mind that tokens are priced per model, not per provider.