feat(mac-locations): VLAN-aware port MAC counts, access/trunk thresholds, likely_attachment

Made-with: Cursor

internal/scans/postgres_store.go

@@ -570,6 +570,36 @@ limit $3`
 	return out
 }
 
+func (s *PostgresStore) CountDistinctMACsPerSwitchPort(scanID string) (map[string]int, error) {
+	query := `
+select ip::text, if_index, bridge_port, vlan,
+  count(distinct lower(replace(trim(coalesce(mac, '')), '-', ':')))::int as c
+from scan_port_devices
+where scan_id = $1
+  and trim(coalesce(mac, '')) <> ''
+group by ip, if_index, bridge_port, vlan`
+	rows, err := s.db.QueryContext(context.Background(), query, scanID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	out := make(map[string]int, 4096)
+	for rows.Next() {
+		var ip string
+		var ifIndex, bridgePort, vlan, c int
+		if err = rows.Scan(&ip, &ifIndex, &bridgePort, &vlan, &c); err != nil {
+			return nil, err
+		}
+		k := PortFDBLocationKey(ip, ifIndex, bridgePort, vlan)
+		out[k] = c
+	}
+	if err = rows.Err(); err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 func (s *PostgresStore) PurgeAllScanData() error {
 	// Дочерние таблицы ссылаются на scan_jobs — CASCADE очищает всё; RESTART IDENTITY сбрасывает bigserial.
 	_, err := s.db.ExecContext(context.Background(), `truncate table scan_jobs restart identity cascade`)