- Snapshot JSON data before yielding batches
- Release lock during batch processing
- Exclude source type from target selection
- Add detailed docstring for lock behavior
- Filter available storage types properly
(cherry picked from commit 5be04263b2)
• Add MongoDB env requirements
• Support config.ini fallback
• Warn on missing env vars
• Check available storage count
• Show config source info
(cherry picked from commit 1a91bcdb5f)