- Partly re-implemented host_to_guest methods from legacy eth_vnet.cc.
- Added two dynamic packet buffers for vnet server replies.
- TFTP and FTP servers are only available if root directory is configured.
- Added TCP port handler methods similar to the UDP ones.
- Added basic TCP connection management and 3-way handshake.
- Added FTP server stub for testing TCP (only login/logout for now).