Add currency settings, Settings service, and dialog to select fiat currency. Add support for non Official currencies like DOGE when using rates.

src/utils/rates/base-rates.ts

@@ -38,19 +38,34 @@ export abstract class BaseRates<
    * @returns The formatted amount.
    */
   public formatCurrency(amount: number, targetCurrency: string): string {
+    const normalizedCurrency = targetCurrency.toUpperCase();
     const minimumFractionDigitsMap: { [currency: string]: number } = {
       AUD: 2,
       BCH: 8,
       USD: 2,
     };
+    const minimumFractionDigits = minimumFractionDigitsMap[normalizedCurrency] ?? 2;
+    const maximumFractionDigits = Math.max(minimumFractionDigits, 8);
 
-    const formatter = new Intl.NumberFormat('en-US', {
-      style: 'currency',
-      currency: targetCurrency,
-      currencyDisplay: 'narrowSymbol',
-      minimumFractionDigits: minimumFractionDigitsMap[targetCurrency] || 0,
-    });
+    try {
+      const formatter = new Intl.NumberFormat('en-US', {
+        style: 'currency',
+        currency: normalizedCurrency,
+        currencyDisplay: 'narrowSymbol',
+        minimumFractionDigits,
+        maximumFractionDigits,
+      });
 
-    return formatter.format(amount);
+      return formatter.format(amount);
+    } catch {
+      // Some numerator symbols from oracle pairs (e.g. DOGE/BCH) are not ISO-4217
+      // fiat currency codes, so Intl currency formatting will throw a RangeError.
+      // In that case we still return a human-readable formatted value.
+      const numericFormatter = new Intl.NumberFormat('en-US', {
+        minimumFractionDigits,
+        maximumFractionDigits,
+      });
+      return `${numericFormatter.format(amount)} ${normalizedCurrency}`;
+    }
   }
 }