Currency Converter
Convert between world currencies using a configurable exchange-rate API.
Not yet connected to a processing engine
Needs a live exchange-rate data source. The UI and API route (/api/tools/currency-rates) are wired up — set TOOLS_EXCHANGE_RATE_API_URL and TOOLS_EXCHANGE_RATE_API_KEY (e.g. from exchangerate-api.com or Open Exchange Rates) to activate it.