Memory leak in Docker container

Container memory usage grows unbounded over time (10GB+), eventually causing OOM or system instability. Requires container restart to recover.

This is a widespread issue affecting many Docker users.

**Potential causes:**
- Python object accumulation
- LFTP process not being cleaned up properly
- File list caching growing unbounded

Ref: ipsingh06/seedsync#107 (27 comments)