feat: Ein-/Auswinterung und Winterverluste je Volk

- WinterCheck per colony, winter and season (autumn/spring), every field
  editable; loss causes limited to the COLOSS monitoring categories.
- Summary per winter and apiary: loss rate lost/wintered, marked
  provisional while colonies are not yet checked in spring - an unchecked
  colony never counts as survived.
- A loss marks the colony deceased only on explicit request, in the same
  transaction and audited.
- Permissions winter-checks:read/create/update granted by migration to
  beekeeper and staff roles; winter checks included in backups.
- Page "Überwinterung": next action first, one button per row until the
  colony is wintered, German number format.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

ApiCore-Frontend/src/lib/winter-checks/winter.spec.ts

@@ -0,0 +1,106 @@
+import { describe, expect, it } from "vitest";
+import type { Colony } from "@/lib/colonies/types";
+import type { WinterCheckWithColony } from "./types";
+import { buildWinterRows, winterLabel, winterYearFor } from "./winter";
+
+function colony(overrides: Partial<Colony>): Colony {
+  return {
+    id: "c1",
+    code: "V-01",
+    apiaryId: "a",
+    hiveType: null,
+    originText: null,
+    colonyType: "PRODUCTION_COLONY",
+    status: "ACTIVE",
+    strength: null,
+    broodStatus: null,
+    feedStatus: null,
+    healthStatus: null,
+    notes: null,
+    currentQueenId: null,
+    createdAt: "",
+    updatedAt: "",
+    deactivatedAt: null,
+    ...overrides,
+  };
+}
+
+const deadColony = {
+  id: "c1",
+  code: "V-01",
+  status: "DECEASED",
+  apiaryId: "a",
+  apiary: { id: "a", name: "Obstwiese" },
+};
+
+function check(overrides: Partial<WinterCheckWithColony>): WinterCheckWithColony {
+  return {
+    id: "w1",
+    colonyId: "c1",
+    userId: "u",
+    winterYear: 2026,
+    season: "AUTUMN",
+    date: "2026-10-01T00:00:00.000Z",
+    occupiedSeams: null,
+    feedStockKg: null,
+    queenPresent: null,
+    outcome: null,
+    lossCause: null,
+    notes: null,
+    createdAt: "",
+    updatedAt: "",
+    colony: { ...deadColony, status: "ACTIVE" },
+    ...overrides,
+  };
+}
+
+describe("winterYearFor / winterLabel", () => {
+  it("maps autumn and spring to the same winter", () => {
+    expect(winterYearFor(new Date(2026, 9, 1))).toBe(2026);
+    expect(winterYearFor(new Date(2027, 2, 20))).toBe(2026);
+    expect(winterLabel(2026)).toBe("Winter 2026/27");
+  });
+});
+
+describe("buildWinterRows", () => {
+  it("lists living colonies without records and hides old dead ones", () => {
+    const groups = buildWinterRows(
+      [colony({ id: "c1" }), colony({ id: "c2", code: "V-02", status: "DECEASED" })],
+      [],
+      new Map([["a", "Obstwiese"]]),
+    );
+    expect(groups).toHaveLength(1);
+    expect(groups[0].rows.map((row) => row.colonyId)).toEqual(["c1"]);
+  });
+
+  it("keeps a colony that died this winter, with its loss record", () => {
+    const groups = buildWinterRows(
+      [],
+      [
+        check({ colony: deadColony }),
+        check({
+          id: "w2",
+          season: "SPRING",
+          outcome: "LOST",
+          lossCause: "DEAD_OR_EMPTY",
+          colony: deadColony,
+        }),
+      ],
+      new Map(),
+    );
+    const [row] = groups[0].rows;
+    expect(row).toMatchObject({ isLiving: false });
+    expect(row.autumn?.id).toBe("w1");
+    expect(row.spring?.outcome).toBe("LOST");
+    expect(groups[0].apiaryName).toBe("Obstwiese");
+  });
+
+  it("sorts colony codes naturally", () => {
+    const groups = buildWinterRows(
+      [colony({ id: "c10", code: "V-10" }), colony({ id: "c2", code: "V-2" })],
+      [],
+      new Map([["a", "Obstwiese"]]),
+    );
+    expect(groups[0].rows.map((row) => row.code)).toEqual(["V-2", "V-10"]);
+  });
+});