Corrupted sessions.json entries (e.g. a bare bool where a dict is
expected) caused TypeError on 'origin' in data' which escaped the
(ValueError, KeyError) inner except and aborted loading ALL remaining
sessions, not just the corrupted one.
Two-layer fix:
- Loop level: isinstance(entry_data, dict) guard before from_dict
- from_dict: isinstance(data['origin'], dict) instead of bare truthiness
- Added TypeError to the inner except as defense-in-depth
Closes#46994
