Drop unused column player_uuid and use only alt_uuid with SQL syntax. Read about the API on the website. (May be updated later, still in development)

When adding a permission to an alt account by name, it couldn’t be added (fixed).

Change database structure
- Improve by removing unused columns
- Add permission command

Change database structure
- Improve by removing unused columns
- Add permission command
Update

Change database structure
- Improve by removing unused columns
- Add permission command

Add multithreading. It not block main thread now.

Add command to change alt nanme with
/identity alt name change [old name] [new name]