fix(auth): align demo staff phone identity and clock-in payload

docs/BACKEND/API_GUIDES/V2/unified-api.md

@@ -114,6 +114,31 @@ Full auth behavior, including staff phone flow and refresh rules, is documented
 - `GET /staff/faqs`
 - `GET /staff/faqs/search`
 
+Example `GET /staff/clock-in/shifts/today` item:
+
+```json
+{
+  "assignmentId": "uuid",
+  "shiftId": "uuid",
+  "title": "Assigned espresso shift",
+  "clientName": "Google Mountain View Cafes",
+  "hourlyRate": 23,
+  "roleName": "Barista",
+  "location": "Google MV Cafe Clock Point",
+  "locationAddress": "1600 Amphitheatre Pkwy, Mountain View, CA",
+  "latitude": 37.4221,
+  "longitude": -122.0841,
+  "startTime": "2026-03-17T13:48:23.482Z",
+  "endTime": "2026-03-17T21:48:23.482Z",
+  "clockInMode": "GEO_REQUIRED",
+  "allowClockInOverride": true,
+  "geofenceRadiusMeters": 120,
+  "nfcTagId": "NFC-DEMO-ANA-001",
+  "attendanceStatus": "NOT_CLOCKED_IN",
+  "clockInAt": null
+}
+```
+
 ### Staff writes
 
 - `POST /staff/profile/setup`