Implements DevTrack #530: Person Presence Intelligence daemon for BigBrother drop implant.
Core components:
- presence_daemon.py: 4 sensor threads (probe, ARP, DHCP, BLE) with exponential decay
- presence_schema.sql: SQLite schema for persons, devices, signals, occupancy log
- install.sh: Deployment script (copies to /opt/sensor/, creates systemd service)
- AUDIT_impl.md: Implementation notes, limitations, audit checklist
Features:
- Exponential decay model (lambda=0.08/min) for signal certainty
- Presence anchor (45-min hold time prevents false VACANT)
- Person state machine: UNKNOWN → PRESENT ↔ ABSENT
- Multi-signal fusion: max + 0.08×min for device aggregate
- Thread-safe in-memory state with SQLite persistence
- Matrix webhook alerting (if configured)
- HTTP status endpoint on 127.0.0.1:9191
- Graceful BLE degrade if bleak unavailable
- No tool fingerprints in output or service names
Cobra