Previously, when no statistics file existed (e.g., first container restart
after adding entities), getStatisticsData() returned null, causing HNSW
rebuild to see entityCount=0 even though entities existed.
This fix ensures all storage adapters return minimal StatisticsData with
totalNodes/totalEdges populated from in-memory counts when statistics files
don't exist yet.
Changes:
- gcsStorage.ts: Return minimal stats instead of null on 404 errors
- memoryStorage.ts: Return minimal stats when statistics is null
- opfsStorage.ts: Return minimal stats on read errors and null checks
- s3CompatibleStorage.ts: Return minimal stats when no statistics found
- fileSystemStorage.ts: Use in-memory counts in mergeStatistics() null case
This completes the GCS persistence fix started in v3.37.3 and ensures
container restarts work correctly in all cloud environments.
Fixes: GCS container restart hang during HNSW index rebuild
David Snelling
968e7daeab