Implement role and user management enhancements

- Added MaxIpLimit to roles, allowing for the configuration of simultaneous IP limits for users.
- Updated role creation and update commands to include MaxIpLimit, ensuring proper handling in the application logic.
- Enhanced user management by introducing a DELETE endpoint for user accounts, with appropriate checks to prevent self-deletion.
- Updated documentation to reflect changes in role and user management, clarifying the new IP limit functionality and user deletion process.
- Adjusted related tests to cover new functionality and ensure robust validation of role and user management features.

backend/src/PnvPanel.Application/Admin/Roles/UpdateRoleCommand.cs

@@ -4,4 +4,4 @@ using PnvPanel.Application.Common.Models;
 
 namespace PnvPanel.Application.Admin.Roles;
 
-public sealed record UpdateRoleCommand(Guid RoleId, int MaxConfigs) : ICommand<Result<RoleDto>>;
+public sealed record UpdateRoleCommand(Guid RoleId, int MaxConfigs, int MaxIpLimit) : ICommand<Result<RoleDto>>;