Add error handling for failures during PBF extraction

[trafficonese]

When running
pbf streets "${PBF_FILE}" >> /data/polylines/extract.osv
the process sometimes terminates unexpectedly due to an out-of-memory (OOM) event, especially when handling large .pbf files.
Currently, the command exits abruptly without a clear error message or structured logging, which makes it difficult to detect and recover from failed extractions in automated pipelines.
This is the current message and it will create an empty extract.0sv.

root@pelias:/data/pelias/docker/projects/porto# pelias prepare polylines
converting /data/openstreetmap/strassennetz.osm.pbf to /data/polylines/extract.0sv
./docker_extract.sh: line 21: 9 Killed pbf streets "${PBF_FILE}" >> /data/polylines/extract.0sv

Expected Behavior
The tool should gracefully handle OOM or other critical errors, ideally by:

• Returning a clear non-zero exit code (e.g., 137 for OOM)
• Writing a concise error message to stderr or a log file
• Not producing partial or corrupted output files