Update the combat system to use `IRunContext` instead of passing
raw inventory objects. This provides a cleaner abstraction for
accessing item data and managing consumed uses.
- Update `canPlayCard` and `payCardCost` to use `IRunContext`
- Pass `IRunContext` through the trigger registration chain
- Fix logic in `canPlayCard` for "uses" cost validation
- Update combat effect tests to use a mock `IRunContext`