server+web: shifts — open/close + signed Z-report (manned mode)

A shift is two signed ledger events, no mutable table: new shift_open event
type + existing shift_z_report. The operator is the logged-in user (carried in
event identity); a shift is open iff their latest shift event is a shift_open.

ShiftService: close sums payment events in [start,end] by tender (cash/card, by
payment time), appends the signed shift_z_report (totals/counts/window), and
prints via a new generic PrinterDevice.printReport(title, lines) (Rongta ESC/POS
text) to a booth-receipt printer. Print is best-effort — a failed print does not
undo the signed close.

Routes (cashier/operator/admin): GET /api/shift/current, POST /api/shift/open
(409 if open), POST /api/shift/close (409 if none). Web ShiftControl in the
shell (non-readonly): Start/End + Z-report totals.

Verified: open -> double-open 409 -> payments (cash+card; one outside the window
excluded) -> close totals correct + signed + printed -> close-again 409 ->
re-open ok; readonly 403; verifyChain ok.

apps/server/src/routes/shift.ts

@@ -0,0 +1,41 @@
+import type { FastifyInstance } from "fastify";
+import { requireRole } from "../auth.js";
+import {
+  NoOpenShiftError,
+  ShiftAlreadyOpenError,
+  type ShiftService,
+} from "../shift-service.js";
+
+// Shift endpoints (manned mode). The operator is the logged-in user; a shift is
+// opened/closed explicitly (not time-based — see wiki/concepts/shift.md and
+// local-jwt-auth.md "until logout"). End Shift signs a shift_z_report + prints it.
+
+export async function shiftRoutes(app: FastifyInstance, shift: ShiftService): Promise<void> {
+  // Cashier/operator/admin run shifts; readonly can't.
+  const guard = requireRole("admin", "operator", "cashier");
+
+  // Is the current operator's shift open? (For the UI to show Start vs. End.)
+  app.get("/api/shift/current", { preHandler: guard }, async (req) => {
+    const operator = req.user.username;
+    const open = shift.openShiftFor(operator);
+    return { operator, open: open ? { startedAt: open.occurredAt } : null };
+  });
+
+  app.post("/api/shift/open", { preHandler: guard }, async (req, reply) => {
+    try {
+      return await shift.open(req.user.username);
+    } catch (err) {
+      if (err instanceof ShiftAlreadyOpenError) return reply.code(409).send({ error: err.message });
+      return reply.code(500).send({ error: (err as Error).message });
+    }
+  });
+
+  app.post("/api/shift/close", { preHandler: guard }, async (req, reply) => {
+    try {
+      return await shift.close(req.user.username);
+    } catch (err) {
+      if (err instanceof NoOpenShiftError) return reply.code(409).send({ error: err.message });
+      return reply.code(500).send({ error: (err as Error).message });
+    }
+  });
+}