Persist per-host scan results and expose hosts endpoint.

Store checked hosts for each scan and add API to fetch host-level up/down probe results.

Made-with: Cursor

internal/scans/postgres_store.go

@@ -280,3 +280,38 @@ where id = $1`
 
 	return current, true
 }
+
+func (s *PostgresStore) SaveHostResult(scanID string, host HostResult) error {
+	query := `
+insert into scan_hosts (scan_id, ip, is_up, checked_at)
+values ($1, $2, $3, $4)`
+	_, err := s.db.ExecContext(context.Background(), query, scanID, host.IP, host.IsUp, host.CheckedAt)
+	return err
+}
+
+func (s *PostgresStore) ListHostResults(scanID string, limit int) []HostResult {
+	if limit <= 0 {
+		limit = 500
+	}
+	query := `
+select ip::text, is_up, checked_at
+from scan_hosts
+where scan_id = $1
+order by checked_at desc
+limit $2`
+	rows, err := s.db.QueryContext(context.Background(), query, scanID, limit)
+	if err != nil {
+		return nil
+	}
+	defer rows.Close()
+
+	out := make([]HostResult, 0, limit)
+	for rows.Next() {
+		var h HostResult
+		if err = rows.Scan(&h.IP, &h.IsUp, &h.CheckedAt); err != nil {
+			return nil
+		}
+		out = append(out, h)
+	}
+	return out
+}