1. Fix the broken logic in (Sorry for including fix commit in same PR, I'm feeling quite tired and would like to go to sleep right away...)
2. Provides new method to obtain credential info for authentication, it will create a temp admin user if SYNO_USE_TEMP_ADMIN is set, instead of requiring the user's own credentials which will be saved in disk.
I do really don't like to have plaintext credentials be saved in disk, and I noticed that you've spent a lot of time fighting with 2FA related stuffs, so why not just get rid of the whole old way. :)
Scruel Tao