feat: scaffold project framework with engine, node skeleton, and passthrough node
- CMake build system with vcpkg dependency management
- libdmf-node: Node interface, port definitions, WebSocket control
server, node runner with MXL lifecycle management
- libdmf-engine: Graph model (nodes/edges CRUD, serialization),
FlowManager (UUID + V210 NMOS flow definitions), ProcessManager
(fork/exec node processes), ApiServer (REST API for graph control)
- Passthrough node: reads V210 grains from MXL, copies, writes to MXL
- Unit tests for Graph and FlowManager (6 cases, 21 assertions)
- MXL SDK as git submodule (symlinked from extern/mxl)
Johanness
5b5ffa1308