refactor: align frontend ownership boundaries

Close audit gaps across API drift, query policy, UI, and tests.

src/shared/lib/display.ts

@@ -0,0 +1,35 @@
+type Money = { currency: string; value: string };
+
+function formatDecimal(value: string): string {
+	const [integer, fraction] = value.split(".");
+	const sign = integer.startsWith("-") ? "-" : "";
+	const grouped = (sign ? integer.slice(1) : integer).replace(
+		/\B(?=(\d{3})+(?!\d))/g,
+		" ",
+	);
+	return `${sign}${grouped}${fraction ? `,${fraction}` : ""}`;
+}
+
+function formatMoney(money: Money | null): string {
+	if (!money) return "—";
+	return `${formatDecimal(money.value)} ${money.currency === "RUB" ? "₽" : money.currency}`;
+}
+
+function formatSnapshotTime(value: string): string {
+	return new Intl.DateTimeFormat("ru-RU", {
+		dateStyle: "medium",
+		timeStyle: "short",
+		timeZone: "UTC",
+	}).format(new Date(value));
+}
+
+const logoSize = 160;
+
+function instrumentLogoUrl(logoName: string | null | undefined): string | null {
+	const stem = logoName?.trim().replace(/\.png$/i, "");
+	return stem
+		? `https://invest-brands.cdn-tinkoff.ru/${stem}x${logoSize}.png`
+		: null;
+}
+
+export { formatMoney, formatSnapshotTime, instrumentLogoUrl };