fix live sortie turn lifecycle parity

packages/logic/test/turnCalendar.test.ts

@@ -0,0 +1,24 @@
+import { describe, expect, it } from 'vitest';
+
+import { getNextTurnAt, type TurnSchedule } from '../src/turn/calendar.js';
+
+describe('turn calendar', () => {
+    it('adds the active turn interval without cutting a general timestamp to a global boundary', () => {
+        const schedule: TurnSchedule = { entries: [{ startMinute: 0, tickMinutes: 10 }] };
+        const current = new Date('2026-07-26T13:38:45.123Z');
+
+        expect(getNextTurnAt(current, schedule).toISOString()).toBe('2026-07-26T13:48:45.123Z');
+    });
+
+    it('uses the interval active at the current timestamp when crossing a schedule segment', () => {
+        const schedule: TurnSchedule = {
+            entries: [
+                { startMinute: 0, tickMinutes: 10 },
+                { startMinute: 14 * 60, tickMinutes: 5 },
+            ],
+        };
+        const current = new Date('2026-07-26T13:58:45.000Z');
+
+        expect(getNextTurnAt(current, schedule).toISOString()).toBe('2026-07-26T14:08:45.000Z');
+    });
+});