The backup validation checked for 'hermes_state.db' and 'memory_store.db'
as telltale markers of a valid Hermes backup zip. Neither name exists in a
real Hermes installation — the actual database file is 'state.db'
(hermes_state.py: DEFAULT_DB_PATH = get_hermes_home() / 'state.db').
A fresh Hermes installation produces:
~/.hermes/state.db (actual name)
~/.hermes/config.yaml
~/.hermes/.env
Because the marker set never matched 'state.db', a backup zip containing
only 'state.db' plus 'config.yaml' would fail validation with:
'zip does not appear to be a Hermes backup'
and the import would exit with sys.exit(1), silently rejecting a valid backup.
Fix: replace the wrong marker names with the correct filename.
Adds TestValidateBackupZip with three cases:
- state.db is accepted as a valid marker
- old wrong names (hermes_state.db, memory_store.db) alone are rejected
- config.yaml continues to pass (existing behaviour preserved)