feat: redesign portfolio position cards

src/entities/portfolio/index.ts

@@ -2,6 +2,7 @@ export type { Portfolio } from "./api/usePortfolio";
 export { usePortfolio } from "./api/usePortfolio";
 export {
 	formatMoney,
+	formatShare,
 	formatSnapshotTime,
 	portfolioErrorCode,
 } from "./model/display";

src/entities/portfolio/model/display.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { formatMoney } from "./display";
+import { formatMoney, formatShare } from "./display";
 
 describe("portfolio display helpers", () => {
 	it("formats decimal strings without financial arithmetic", () => {
@@ -10,4 +10,27 @@ describe("portfolio display helpers", () => {
 		expect(formatMoney({ value: "0.5", currency: "USD" })).toBe("0,5 USD");
 		expect(formatMoney(null)).toBe("—");
 	});
+
+	it("formats a share as a display-only percentage", () => {
+		expect(
+			formatShare(
+				{ currency: "RUB", value: "150" },
+				{ currency: "RUB", value: "1000" },
+			),
+		).toBe("15 %");
+		expect(
+			formatShare(
+				{ currency: "RUB", value: "123.45" },
+				{ currency: "RUB", value: "999.99" },
+			),
+		).toBe("12,3 %");
+		expect(formatShare(null, { currency: "RUB", value: "100" })).toBeNull();
+		expect(formatShare({ currency: "RUB", value: "100" }, null)).toBeNull();
+		expect(
+			formatShare(
+				{ currency: "RUB", value: "100" },
+				{ currency: "RUB", value: "0" },
+			),
+		).toBeNull();
+	});
 });

src/entities/portfolio/model/display.ts

@@ -17,6 +17,21 @@ export function formatMoney(money: Money | null): string {
 	return `${formatDecimal(money.value)} ${money.currency === "RUB" ? "₽" : money.currency}`;
 }
 
+export function formatShare(
+	numerator: Money | null,
+	denominator: Money | null,
+): string | null {
+	if (!numerator || !denominator) return null;
+	const total = Number(denominator.value);
+	if (!Number.isFinite(total) || total <= 0) return null;
+	const percent = (Number(numerator.value) / total) * 100;
+	if (!Number.isFinite(percent)) return null;
+	const rounded = new Intl.NumberFormat("ru-RU", {
+		maximumFractionDigits: 1,
+	}).format(percent);
+	return `${rounded} %`;
+}
+
 export function formatSnapshotTime(value: string): string {
 	return new Intl.DateTimeFormat("ru-RU", {
 		dateStyle: "medium",