money: wishlist tier totals fit on one line (compact €, scales with card, exact amount in tooltip)

src/lib/money-tracker/wishlist.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest';
-import { sortWishlist, tierClass } from './wishlist';
+import { compactAmount, compactEuro, sortWishlist, tierClass } from './wishlist';
 
 describe('wish list order', () => {
 	it('sorts by tier descending, then price descending, unpriced and untiered last', () => {
@@ -23,4 +23,19 @@ describe('wish list order', () => {
 		expect(tierClass(null)).toBe('tier-none');
 		expect(tierClass(9)).toBe('tier-none');
 	});
+
+	it('formats tier totals compactly', () => {
+		expect(compactEuro(0)).toBe('€\u00a00');
+		expect(compactEuro(500_00)).toBe('€\u00a0500');
+		expect(compactEuro(8_865_00)).toBe('€\u00a08.865');
+		expect(compactEuro(9_365_49)).toBe('€\u00a09.365');
+		expect(compactEuro(9_999_60)).toBe('€\u00a010k');
+		expect(compactEuro(17_580_00)).toBe('€\u00a017,6k');
+		expect(compactEuro(28_080_00)).toBe('€\u00a028,1k');
+		expect(compactEuro(999_960_00)).toBe('€\u00a01M');
+		expect(compactEuro(1_234_567_00)).toBe('€\u00a01,2M');
+		expect(compactEuro(-1_500_00)).toBe('−€\u00a01.500');
+		expect(compactAmount(28_080_00)).toBe('28,1k');
+		expect(compactAmount(-40)).toBe('0');
+	});
 });

src/lib/money-tracker/wishlist.ts

@@ -23,3 +23,27 @@ export function sortWishlist<T extends WishSortable>(items: readonly T[]): T[] {
 export function tierClass(priority: number | null): string {
 	return priority != null && priority >= 1 && priority <= 5 ? `tier-${priority}` : 'tier-none';
 }
+
+const oneDecimal = (value: number) => {
+	const rounded = Math.round(value * 10) / 10;
+	return (Number.isInteger(rounded) ? String(rounded) : rounded.toFixed(1)).replace('.', ',');
+};
+
+/**
+ * Short amount for the wish list tier cards, so a total fits on one line:
+ * whole euros below €10k ("8.865"), then thousands ("28,1k") and millions ("1,2M").
+ * Uses the same en-NL separators as the rest of the tracker. No currency symbol.
+ */
+export function compactAmount(cents: number): string {
+	const euros = Math.round(Math.abs(cents) / 100);
+	const sign = cents < 0 && euros > 0 ? '−' : '';
+	if (euros >= 999_950) return `${sign}${oneDecimal(euros / 1_000_000)}M`;
+	if (euros >= 10_000) return `${sign}${oneDecimal(euros / 1_000)}k`;
+	return sign + String(euros).replace(/\B(?=(\d{3})+(?!\d))/g, '.');
+}
+
+/** compactAmount with the euro sign: "€ 8.865", "€ 28,1k", "−€ 1.500". */
+export function compactEuro(cents: number): string {
+	const body = compactAmount(cents);
+	return body.startsWith('−') ? `−€\u00a0${body.slice(1)}` : `€\u00a0${body}`;
+}