The `sshmngr` service failed to list active sessions with the `sshd`
(OpenSSH) backend because the session detection logic could not handle
the process structure of modern OpenSSH, which uses an intermediate
process for new connections.
This commit resolves the issue by:
- Improving process lookup to check for grandparent PIDs, correctly
identifying the session process.
- Querying the correct intermediate process for network connection details.
parse netstat output.
The new logic is encapsulated in a `get_network_info` function within the
`openssh` backend script to maintain compatibility with the `dropbear`
backend, which uses a simpler implementation of the same function.
* sshmngr uci is deprecated and so are the library functions
related to managing that uci, sshmngr will directly interact
with the backend uci now
* a compile time flag is introduced which tells sshmngr code
whether dropbear backend is being used or not
Make the backend daemon configurable, please note, still need
to disable dropbear as default in config and choose the backend
based on config in sshmngr
