- 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,
- Rename internal/service to internal/services in carrier-connector
- Update service imports in selection_integration.go and smdp_integration.go
- Move currency repository files from internal/currency to internal/repository
- Move rate plan repository files from internal/rateplan to internal/repository
- Update package declarations and imports for currency domain types
- Add currency package imports
- Add CurrencyHandler struct with billing service, exchange service, and logger fields
- Add ConvertCurrency endpoint with JSON binding and amount conversion support
- Add GetExchangeRate endpoint with currency pair path parameters
- Add ProcessBilling endpoint with billing request validation and transaction processing
- Add GetBillingHistory with profile ID filtering, date range, limit, and offset support
- Add GormRepository with CRUD operations for currencies, exchange rates, and transactions
- Add repository helper methods for model-to-domain conversions with JSON metadata handling
- Add GetHistoricalRates with date range filtering and chronological ordering
- Add ListExchangeRates with currency pair, active status, and date range filtering
- Add CreateTransaction, GetTransaction, UpdateTransaction, and List
- Add RatePlanCurrencyIntegrator struct with billing service, exchange service, rate plan service, logger, and base currency fields
- Add NewRatePlanCurrencyIntegrator constructor with dependency injection
- Add SubscribeToPlanWithCurrency with price conversion, subscription creation, and initial billing processing
- Add CalculatePlanCostInCurrency with base cost calculation
- Move Repository, ExchangeRateProvider, BillingService, and AnalyticsService interfaces from types.go to new interface.go
- Move BillingSummary and CurrencyUsageStats structs to interface.go
- Move CurrencyModel, ExchangeRateModel, and TransactionModel to new models.go
- Move GORM hooks (BeforeCreate, BeforeUpdate) and TableName methods to models.go
- Remove redundant comments from exchange_rate_service.go
- Add ExchangeRateService struct with repository, logger, providers, and base currency fields
- Add NewExchangeRateService constructor and AddProvider for provider registration
- Add GetExchangeRate with repository caching, provider fallback, and same-currency handling
- Add ConvertAmount wrapper with exchange rate retrieval and amount calculation
- Add RefreshRates with multi-provider rate
- Add BillingServiceImpl struct with repository, exchange service, logger, and base currency fields
- Add NewBillingService constructor with dependency injection
- Add ProcessBilling with request validation, currency conversion, transaction creation, and payment processing
- Add ConvertAmount wrapper delegating to exchange service
- Add GetBillingHistory with profile ID filtering and transaction retries