fix: clarify currencies in mixed budget legend

src/ui/components/BudgetTree.test.tsx

@@ -9,6 +9,7 @@ import { createSeedDataset } from "../../domain/seed.ts";
 import { addBudgetFolder, addRecurringCost, confirmOccurrence } from "../../store/actions.ts";
 import { monthView } from "../../domain/views.ts";
 import { store } from "../../store/index.ts";
+import { PostTableLegend } from "./PostTable.tsx";
 import { BudgetTree } from "./BudgetTree.tsx";
 
 function setup(run: (container: HTMLDivElement, billId: string) => void, confirm = false) {
@@ -21,7 +22,7 @@ function setup(run: (container: HTMLDivElement, billId: string) => void, confirm
   if (confirm) confirmOccurrence(data, bill.id, "2026-09", { date: "2026-09-01" });
   const original = { get: store.get, subscribe: store.subscribe }; store.get = () => data; store.subscribe = () => () => {};
   const container = document.createElement("div"); document.body.append(container); const root = createRoot(container);
-  try { act(() => root.render(<MemoryRouter><BudgetTree monthId="2026-09" rows={monthView(data, "2026-09").rows} /></MemoryRouter>)); run(container, bill.id); }
+  try { act(() => root.render(<MemoryRouter><PostTableLegend baseCurrency="DKK" /><BudgetTree monthId="2026-09" rows={monthView(data, "2026-09").rows} /></MemoryRouter>)); run(container, bill.id); }
   finally { act(() => root.unmount()); container.remove(); Object.assign(store, original); }
 }
 function housing(container: HTMLDivElement) { return container.querySelector('button[aria-label="Housing"]') as HTMLButtonElement; }
@@ -48,3 +49,11 @@ test("bill edit reaches its settings row", () => setup((container, billId) => {
   expect(container.textContent).toContain("Ended");
   expect(container.textContent).toContain("Next 2028-03");
 }, true));
+
+test("legend scopes base currency to post figures and identifies bill currencies", () => setup(container => {
+  const legend = container.querySelector("span.flex.flex-wrap")!;
+  expect(legend.textContent).toContain("Post figures in DKK.");
+  expect(legend.textContent).toContain("Bill prices show their own currency.");
+  expect(legend.textContent).toContain("Projected subtracts bills not yet confirmed.");
+  expect(legend.textContent).not.toContain("All figures");
+}));