Relates to https://github.com/shaarli/Shaarli/issues/324
Added:
- Add the `LoginManager` class to manage logins and bans
Changed:
- Refactor IP ban management
- Simplify logic
- Avoid using globals, inject dependencies
Fixed:
- Use `ban_duration` instead of `ban_after` when setting a new ban
Signed-off-by: VirtualTam <virtualtam@flibidi.net>
