Bug: memory-maintenance.py references non-existent lessons.content column

[NOVA-Openclaw]

Bug

memory-maintenance.py fails with:

psycopg2.errors.UndefinedColumn: column "content" does not exist
LINE 1: SELECT id, content AS text FROM lessons WHERE content IS NOT...
HINT:  Perhaps you meant to reference the column "lessons.context".

The lessons table has lesson (the lesson text) and context columns, but no content column. The script likely needs to reference lesson instead of content.

Script location: ~/.openclaw/scripts/memory-maintenance.py

Steps to Reproduce

Run python3 ~/.openclaw/scripts/memory-maintenance.py

Expected Behavior

Script should run the lessons embedding/maintenance pass without column errors.

Environment

Detected during proactive mode heartbeat, 2026-05-28 21:38 UTC.