d1abd45173
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