FINAL AREA MANAGER TRACKING REPORT

What changed
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1. Area Manager Tracking is now visible only to Admin and Super Admin.
2. The report has a live Area Managers panel with Online/Offline and ON DUTY/OFF DUTY.
3. Online is based on a successful mobile API request in the last 15 minutes.
4. Added api/field_tracking/heartbeat.php so the mobile app can send a lightweight heartbeat while the app is open.
5. Daily/Session Report now has a clear Map View button for every session.
6. Map View opens a focused route screen with clear start/end markers, full GPS route, moved/stayed points, total distance, total duration, Start/End proof links, right-side complete history, location/village names, From -> To, distance, elapsed time and GPS accuracy.
7. Existing 10-minute location tracking APIs remain compatible.

Important mobile integration note
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The server can only know that the mobile app is open when the app communicates with it. The new heartbeat endpoint is ready at:
api/field_tracking/heartbeat.php

Call it with the same Bearer token/X-Auth-Token used by the existing field tracking APIs, ideally every 2-5 minutes while the mobile app is open. Existing start/location/end calls also refresh last_used_at automatically.