V192 focused regression report

19 tests passed.

Verified:
- V176 Import/Export Lua functions remain byte-identical.
- V176 CHARGEN_IMPORT / CHARACTER / CHARACTER_EXPORT / CHARGEN_EXPORT / CHARGEN_NAME menus remain byte-identical.
- V176 account_folder_router.py remains byte-identical.
- Login activation is per account.
- LOG OUT clears only the leaving account's Activate flag.
- Quit to Main Menu clears only the leaving account before the native BG2 quit action.
- Full BG2 shutdown clears only the leaving account before Infinity_ShutdownGame().
- Quit paths also clear the local authenticated session.
- Installer clears stale V191/V192 Activate=1 values once while BG2 is closed.
- Stale-flag cleanup does not touch account/password records or character data.
- No automatic character backup/restore behavior was added.
