The DB owner-rename loop in rename_user patched every SQL column named
owner, but three non-SQL stores were left behind:
1. session_manager.sessions -- in-memory Session objects carry s.owner
set at server-boot time. get_sessions_for_user() does an exact
s.owner == username check, so the renamed user chat sidebar goes empty
until a server restart.
2. data/deep_research/*.json -- each completed research report is a
standalone JSON file with an owner field. research_routes filters
by d.get(owner) == user, making every report invisible to the
renamed user.
3. data/memory.json -- a flat JSON array; each entry carries an owner
field. memory_manager.load(owner=user) filters on it, so all memories
vanish from the memory panel.
Fix: after the SQL loop, patch all three:
- iterate sm.sessions and update owner in-place (exposed via app.state)
- walk data/deep_research/*.json and rewrite owner with atomic_write_json
- update matching entries in memory.json with atomic_write_json
All three use the same case-insensitive lower() comparison the SQL loop
already uses. Each step is independently wrapped so a single failure
does not abort the others or the rename itself.
Fixes#3362
Ashvin