**Implementation Started**:
- Added scp_input_buffer field to Channel struct (3 locations)
- Field initialization in all Channel creation
- Build successful (181 warnings)
**Testing**:
- SCP 2MB still fails (expected, handler logic not modified)
- Connection closed by remote host
- Need to modify scp_handler.rs next
**Next Steps**:
- Modify scp_handler.rs handle_file_command()
- Use scp_input_buffer for data accumulation
- Similar to SFTP accumulation logic (Phase 14.3)
**Progress**: Phase 14.4 started (50% complete)
**Tool Calls**: Reached 200 limit, session ending
