Add savings chat analysis feature

src/components/charts/CategoryBreakdownChart.test.ts

@@ -0,0 +1,36 @@
+import { describe, expect, test } from "vitest";
+import { toCategoryPieData } from "./categoryBreakdownData";
+
+describe("toCategoryPieData", () => {
+  test("uses positive chart values while preserving signed expense amounts", () => {
+    expect(
+      toCategoryPieData([
+        {
+          name: "Lebensmittel",
+          amount: -123.45,
+          color: "#ef4444",
+          block: "variabel",
+        },
+        {
+          name: "Rueckerstattung",
+          amount: 12,
+          color: "#22c55e",
+        },
+      ]),
+    ).toEqual([
+      {
+        name: "Lebensmittel",
+        amount: -123.45,
+        chartAmount: 123.45,
+        color: "#ef4444",
+        block: "variabel",
+      },
+      {
+        name: "Rueckerstattung",
+        amount: 12,
+        chartAmount: 12,
+        color: "#22c55e",
+      },
+    ]);
+  });
+});