- Renamed TOPO_BGP to TOPO_GROUP with topo_group_id (64bit)
- Added TOPO_GROUPS container (ll_queue group_list) in UTUN_INSTANCE
- Memory pools moved from TOPO_GROUP to TOPO_GROUPS (instance-level)
- Default group: TOPO_GROUP_UTUN = 0x8000000000000000
- topo_groups_get_default() searches by group_id, not just first entry
- All topo_bgp_* renamed to topo_group_*; function signatures updated
- Files: topo_bgp.h/c -> topo_group.h/c
- Add NodeConfig: simplified INI config manager for embedded uTun node
- X25519 key generation via OpenSSL EVP
- Random node_id generation
- addServer/removeServer, addClient/removeClient API
- Auto-creates config with default server on first run
- Integrate UtunNode into MainWindow:
- Creates NodeConfig in ~/.config/chatgui/node.conf
- Starts embedded uTun node (no TUN, no msg_transport)
- In separate thread with uasync_poll event loop
- Replace MsgClient (TCP IPC) with UtunNode (direct calls):
- ChatPropagator now uses UtunNode for send/recv
- send(uint64_t, QByteArray) replaces sendTo
- messageReceived signal replaces received signal
- MainWindow cleanup: remove MsgClient, add UtunNode+NodeConfig
- UtunNode runs uTun instance in a dedicated std::thread
- no TUN, no msg_transport — direct etcp_route_send/recv calls
- Thread-safe cross-thread communication via Qt signals
- C callback (etcp_recv_fn) stores UtunNode* via thread_local
- etcp_router_bind on service ID 0x11 for chat messages
- uasync_poll(100ms) loop runs until stop() called