- Update BillingSummary.Breakdown field type from map[string]interface{} to map[string]any
- Update Transaction.Metadata field type from map[string]interface{} to map[string]any
- Update RatePlanCurrencyIntegrator subscription and billing metadata to use map[string]any
- Update handler request/response types to use map[string]any (CreateRatePlanRequest, UpdateRatePlanRequest,