feat: support default API rate limiting policy with Polly (#46)

- Add new `IGDBClient.CreateWithDefaults` static helper to create an IGDB client configured with all the defaults
- Add default Polly API policy to `IGDB.ApiPolicy` static class and `DefaultApiPolicy` async policy
- Add an overload for passing an `IAsyncPolicy<HttpResponseMessage>` to the client constructor

feat(api): Add PopScore endpoints (#39)

* Add PopScore endpoints

Co-authored-by: Kamran Ayub <[email protected]>

Add QueryWithResponse API (#38)

fix: use concurrent dictionary

June 2024: Performance and API updates (#36)

May 2024: Remove deprecated APIs for August 2024 update (#35)

fix: support for ExpandedGames

feat: Add /dumps endpoint (#34)

feat: Oct 2023 API updates (#29)

Co-authored-by: Michael Green <[email protected]>

fix: typo in Game Category Episode (#25)