- stcp_server_create: support AF_INET and AF_INET6 V6ONLY=1 (no dual-stack)
- Add listen_family to stcp_link_config
- init_sockets: return error (not partial) on any bind failure
- add chat_core_sync_my_addresses() call at chatgui startup
- collect_my_addrs: add proto byte (1=UDP, 2=TCP) to binary format
- chat_sync.c JOIN/WELCOME/PEER_UPSERT: read proto byte, write protocol column
- member_sync.c: read proto byte, dynamic protocol bind
- topo_node.c: debug logs for nodeinfo changed detection
- node_config.cpp: type=public for all servers