List every macroeconomic indicator FXMacroData publishes for a currency, with units, frequency, and coverage/freshness metadata. ALWAYS call this first when the user asks about a country's macro data — it returns the exact `indicator` slug strings to pass to indicator_query, release_calendar, and indicator_visual_artifact. Check `coverage` before calling indicator_query; stale, partial, or unavailable rows are not suitable for real-time carry or inflation analysis. Supported currencies (lowercase 3-letter codes): AUD, BRL, CAD, CHF, CNH, CNY, DKK, EUR, GBP, ILS, JPY, NGN, NOK, NZD, PEN, SEK, THB, USD.