db96a02f89
- Implemented 3 Commands with handlers and validators:
* JoinNetworkCommand: Add user to binary network tree
- Validates parent exists and is in network
- Validates leg position is empty
- Records history with NetworkMembershipAction.Join
* MoveInNetworkCommand: Move user to different position
- Validates new parent and leg availability
- Prevents circular dependencies (IsDescendant check)
- Records old/new parent and leg in history
* RemoveFromNetworkCommand: Remove user from network
- Validates no children exist (must move/remove first)
- Soft delete (sets NetworkParentId to null)
- Idempotent design
- Implemented 3 Queries with handlers, validators, and DTOs:
* GetNetworkTreeQuery: Binary tree visualization
- Recursive tree building with MaxDepth limit (1-10)
- Returns nested structure with Left/Right children
* GetUserNetworkPositionQuery: User position details
- Parent info, leg position, children counts
- Left/Right child counts for balance view
* GetNetworkMembershipHistoryQuery: Complete audit trail
- Filter by UserId, pagination support
- Shows Join/Move/Remove actions with full details
- All operations include complete history tracking
- Binary tree validation (parent-child relationships)
- Circular dependency prevention in MoveInNetwork
- 21 new files, ~850 lines of code
- Build successful with 0 errors