test(server): Phase 1 — server-core suites (occupancy, pay, exit, shift)

Completes the anti-fraud/safety core coverage on a fresh in-memory DB:

- occupancy.test.ts (12): the ledger-fold count, the capacity/full gate, and the
  reserved-subscriber-spots model — never double-count a parked subscriber, reserve
  tightens only the TRANSIENT gate.
- pay-station.test.ts (12): quote math against the frozen tariff, the signed-payment
  side effect (+ chain verify), no-session / no-tariff errors, the booth lookup view,
  active-session listing.
- exit-flow.test.ts (9): the GATE — refuse unknown / unpaid / grace-expired (no exit
  signed); a paid-within-grace session signs the exit; the booth transient path has NO
  subscription bypass; a prepaid subscriber leaves via the assist (reopenBarrier) path.
- shift-service.test.ts (14): site-wide single-open invariant, the takings SPLIT by
  source (subscription sales vs out-of-window vs transient tickets), drawer carry-
  forward + cash_in/out vouchers, Z-report sign + listShifts read-back.
- entry-flow.test.ts (5): the exported validateTicketCode Luhn typo-guard. (The
  capacity-gate/print-hold/sign-before-open paths need device fakes — covered in the
  device + route phases.)

Adds test-helpers.ts (real EventLog, silent logger, tariff seeder). server 68/68 green.

Note: apps/vision has 2 PRE-EXISTING failures (test_app.py) — environment drift now
that fast_alpr + the ONNX model are installed (the "stub mode" assertions are stale).
Untouched here; to be fixed in the vision phase.

Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V

apps/server/src/shift-service.test.ts

@@ -0,0 +1,164 @@
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { createTestDb } from "@parking/db/testing";
+import { type Db } from "@parking/db";
+import {
+  ShiftService,
+  ShiftAlreadyOpenError,
+  NoOpenShiftError,
+  NoShiftOpenError,
+  InvalidCashMovementError,
+} from "./shift-service.js";
+import type { EventLog } from "./event-log.js";
+import { makeLog, silentLogger } from "./test-helpers.js";
+
+// The shift is an operator's accountability period — signed shift_open … shift_z_report,
+// no mutable table. These tests pin: the site-wide single-open invariant, the takings
+// SPLIT by source (subscription sales vs out-of-window charges vs transient tickets — the
+// 2026-06-21 work), the drawer carry-forward, and that close signs a Z-report with the
+// right figures.
+
+let db: Db;
+let close: () => void;
+let log: EventLog;
+let shift: ShiftService;
+
+beforeEach(() => {
+  const t = createTestDb();
+  db = t.db;
+  close = t.close;
+  log = makeLog(db);
+  shift = new ShiftService(db, log, silentLogger());
+});
+afterEach(() => close());
+
+/** Append a signed payment with source-split flags, as the booth/pay paths do. */
+async function payment(
+  amountMinor: number,
+  opts: { tender?: "cash" | "card"; subscriptionSale?: boolean; subscriptionWindowCharge?: boolean } = {},
+) {
+  await log.append({
+    type: "payment", source: "manual", identity: "T",
+    payload: {
+      sessionRef: "T", amountMinor, currency: "ALL", tender: opts.tender ?? "cash",
+      ...(opts.subscriptionSale ? { subscriptionSale: true } : {}),
+      ...(opts.subscriptionWindowCharge ? { subscriptionWindowCharge: true } : {}),
+    },
+  });
+}
+
+describe("single-open invariant", () => {
+  it("opens a shift and reports it as the current open one", async () => {
+    await shift.open("alice");
+    const cur = shift.currentOpenShift();
+    expect(cur?.identity).toBe("alice");
+  });
+
+  it("refuses a second open while one is already open (even another operator)", async () => {
+    await shift.open("alice");
+    await expect(shift.open("alice")).rejects.toBeInstanceOf(ShiftAlreadyOpenError);
+    await expect(shift.open("bob")).rejects.toBeInstanceOf(ShiftAlreadyOpenError);
+  });
+
+  it("allows a new shift after the prior one closes", async () => {
+    await shift.open("alice");
+    await shift.close("alice");
+    await expect(shift.open("bob")).resolves.toBeTruthy();
+  });
+
+  it("close without an open shift throws", async () => {
+    await expect(shift.close("alice")).rejects.toBeInstanceOf(NoOpenShiftError);
+  });
+
+  it("requireOpenShift throws when none is open", () => {
+    expect(() => shift.requireOpenShift()).toThrow(NoShiftOpenError);
+  });
+});
+
+describe("takings split by source", () => {
+  it("separates subscription sales, out-of-window charges, and transient tickets", async () => {
+    await shift.open("alice");
+    await payment(50000, { subscriptionSale: true }); // monthly fee
+    await payment(20000, { subscriptionWindowCharge: true }); // out-of-window
+    await payment(10000); // transient ticket
+    await payment(30000, { tender: "card" }); // transient ticket, card
+
+    const r = shift.currentReport()!;
+    expect(r.subscriptionSalesMinor).toBe(50000);
+    expect(r.subscriptionWindowMinor).toBe(20000);
+    expect(r.subscriptionTotalMinor).toBe(70000);
+    expect(r.ticketTotalMinor).toBe(40000); // 10000 cash + 30000 card
+    // The split must reconcile to the cash+card grand total.
+    expect(r.cashTotalMinor + r.cardTotalMinor).toBe(
+      r.ticketTotalMinor + r.subscriptionTotalMinor,
+    );
+    expect(r.cashTotalMinor).toBe(80000); // 50000 + 20000 + 10000
+    expect(r.cardTotalMinor).toBe(30000);
+  });
+});
+
+describe("drawer carry-forward", () => {
+  it("cash payments enter the drawer; card does not", async () => {
+    await shift.open("alice");
+    await payment(10000, { tender: "cash" });
+    await payment(50000, { tender: "card" });
+    const r = shift.currentReport()!;
+    expect(r.cashTotalMinor).toBe(10000);
+    // Expected drawer = opening(0) + cash(10000) + added(0) − removed(0).
+    expect(r.expectedDrawerMinor).toBe(10000);
+  });
+
+  it("a closed shift's expected drawer becomes the next shift's opening float", async () => {
+    await shift.open("alice");
+    await payment(25000, { tender: "cash" });
+    const closed = await shift.close("alice");
+    expect(closed.expectedDrawerMinor).toBe(25000);
+
+    const next = await shift.open("bob");
+    expect(next.openingFloatMinor).toBe(25000); // inherited
+  });
+
+  it("cash_in / cash_out vouchers adjust the drawer", async () => {
+    await shift.open("alice");
+    await shift.recordVoucher({ type: "cash_in", operator: "alice", authorizedBy: "admin", amountMinor: 100000, reason: "float load" });
+    await shift.recordVoucher({ type: "cash_out", operator: "alice", authorizedBy: "admin", amountMinor: 30000, reason: "bank drop" });
+    const r = shift.currentReport()!;
+    expect(r.cashAddedMinor).toBe(100000);
+    expect(r.cashRemovedMinor).toBe(30000);
+    expect(r.expectedDrawerMinor).toBe(70000);
+  });
+
+  it("rejects a non-positive voucher amount", async () => {
+    await shift.open("alice");
+    await expect(
+      shift.recordVoucher({ type: "cash_in", operator: "alice", authorizedBy: "admin", amountMinor: 0, reason: "x" }),
+    ).rejects.toBeInstanceOf(InvalidCashMovementError);
+    await expect(
+      shift.recordVoucher({ type: "cash_out", operator: "alice", authorizedBy: "admin", amountMinor: -5, reason: "x" }),
+    ).rejects.toBeInstanceOf(InvalidCashMovementError);
+  });
+});
+
+describe("close signs a Z-report; listShifts reads it back", () => {
+  it("a closed shift appears in history with its split figures", async () => {
+    await shift.open("alice");
+    await payment(50000, { subscriptionSale: true });
+    await payment(10000); // ticket
+    await shift.close("alice");
+
+    const history = shift.listShifts();
+    expect(history).toHaveLength(1);
+    const s = history[0];
+    expect(s.operator).toBe("alice");
+    expect(s.subscriptionSalesMinor).toBe(50000);
+    expect(s.ticketTotalMinor).toBe(10000);
+    expect(s.cashTotalMinor).toBe(60000);
+    // The Z-report is a signed chain event.
+    expect(log.verifyChain()).toEqual({ ok: true });
+  });
+
+  it("filters history by operator", async () => {
+    await shift.open("alice"); await shift.close("alice");
+    await shift.open("bob"); await shift.close("bob");
+    expect(shift.listShifts({ operator: "alice" }).map((s) => s.operator)).toEqual(["alice"]);
+  });
+});