V164 - BACKGROUND NATIVE EXPORT RETRY

1. Fixes V163 background autosave checking IsExportButtonClickable() before BG2 was in the Character/Record context.
2. The script now selects the accepted character, opens BG2 Character/Export internally, exports to reserved __DASV__, and closes the panels in the same background pass.
3. The router atomically renames/replaces __DASV__ as the stable account id (dra_1, dra_2, kro_1, ...).
4. First save is attempted almost immediately after the stable id is returned.
5. If the character/export backend is not ready yet, the script retries every 2 seconds initially, then backs off.
6. Autosave router timeouts are recoverable and retry instead of leaving autosave permanently busy.
7. A pulse also runs on MP_MODIFYCHARACTER, plus MULTIPLAYER and WORLD_ACTIONBAR.
8. Manual Export Character stays hidden; Import Character stays native/account-mirrored.
9. Import Saved Game/pregenerate stay disabled.
10. No automatic character backup/history copies are created. Deleted live stable files still stop autosave instead of respawning.
