feature to persist the downloaded subtitle

I believe we need an option in the settings that enables us to persist the downloaded subtitles in the system for a long time instead of the temp folder.

If you agree, I can implement this feature

Start by locating the plugin's settings handling and the code that downloads subtitles into the temp folder. Confirm how settings are stored and where downloaded files are created; done means a user-configurable option persists subtitles beyond temporary storage.

Written by the indexing model from the issue text.