SLAM Engine needs to set flag in drone HASH table

[teiszler]

In terraslam.py, in addition to setting the lat/lon/alt/pose in the Redis STREAM, we also need to set the 'slam_registering' key in the drone's HASH table.

if slam_status == "success" and self.slam_client.latest_pose:
# Get GPS coordinates
lat, lon, alt = self.slam_client.latest_pose

        logger.info(f"GPS coordinates: {lat}, {lon}, {alt}")
        # Store in Redis
        self.r.xadd(
            "slam",
            {
                "pose_x": 0.0,
                "pose_y": 0.0,
                "pose_z": 0.0,
                "lat": str(lat),
                "lon": str(lon),
                "alt": str(alt)
            }
        )