feat(ui): add dynamic amount currency prefix, normalize fiat symbols, and simplify data source badge

lib/currency-display.ts

@@ -0,0 +1,38 @@
+import { AssetType } from "@/lib/assets";
+
+interface DisplayAsset {
+  code: string;
+  type: AssetType;
+  symbol?: string;
+}
+
+const FIAT_DISPLAY_SYMBOLS: Record<string, string> = {
+  USD: "$",
+  EUR: "€",
+  GBP: "£",
+  JPY: "¥",
+  PLN: "zł",
+  CHF: "CHF",
+  CAD: "C$",
+  AUD: "A$",
+  NZD: "NZ$",
+  CNY: "¥",
+  INR: "₹",
+  KRW: "₩",
+  TRY: "₺",
+  BRL: "R$",
+  MXN: "MX$",
+  THB: "฿"
+};
+
+export function getDisplaySymbol(asset?: DisplayAsset): string | undefined {
+  if (!asset) {
+    return undefined;
+  }
+
+  if (asset.type === "fiat") {
+    return FIAT_DISPLAY_SYMBOLS[asset.code] ?? asset.symbol ?? asset.code;
+  }
+
+  return asset.symbol ?? asset.code;
+}