- Add subscribe traffic_limit schema and migration\n- Support traffic_limit in admin create/update and list/details\n- Apply traffic_limit when building server user list speed limits\n- Add public user traffic stats API
- Node group CRUD operations with traffic-based filtering
- Three grouping modes: average distribution, subscription-based, and traffic-based
- Automatic and manual group recalculation with history tracking
- Group assignment preview before applying changes
- User subscription group locking to prevent automatic reassignment
- Subscribe-to-group mapping configuration
- Group calculation history and detailed reports
- System configuration for group management (enabled/mode/auto_create)
Database:
- Add node_group table for group definitions
- Add group_history and group_history_detail tables for tracking
- Add node_group_ids (JSON) to nodes and subscribe tables
- Add node_group_id and group_locked fields to user_subscribe table
- Add migration files for schema changes
