Experimental CAN support tested via Waveshare's esp32-s3-lcd-4.3-board

[brainstorm]

That is https://docs.waveshare.com/ESP32-S3-Touch-LCD-4.3 (thanks E for the donation!)

Implements CAN support over a SSH session (slcan format for now), that is:

INFO - SSH server ident: SSH-2.0-Sunset-0.5.0-ssh-stamp-0.3.0
INFO - WIFI PSK: 98yiehO8Z1g1JzwzY4YiTITP
INFO - WIFI MAC: DC:DA:0C:54:BF:18
INFO - SSH hostkey fingerprint: SHA256:hxlqdkiJvoRSot24LZtmD6Mpp5clfuORwnbaqFfpmlw
INFO - WIFI AP band: Band2_4G (channel 1)
INFO - Wifi configuring Access Point Mode
INFO - Connect to the AP `TPNaZM6BzCAWKNVH` with IP 192.168.4.1/24
INFO - Station connected: ConnectedInfo { mac: [60, 100, 207, 39, 52, 225], aid: 1, is_mesh_child: false }
INFO - Handling CAN session
INFO - Starting CAN bridge
WARN - TWAI TX unacknowledged, aborting retransmission (is another CAN node connected?)
WARN - TWAI TX unacknowledged, aborting retransmission (is another CAN node connected?)

And on the client side state -s for session (OBS: weird ordering of the -s and can arguments, I know, but that's how SSH client works):

$ ssh -s zssh@192.168.4.1 can
t1238AABBCCDDEEFF1234

[jubeormk1]

I must say that it is interesting how this new interface has been added. It opens the use of many interfaces.

The last mile to get the final connection with the peripheral pins is complicated, getting the pins for SCA, SCL and the maps in toml are points that would be great to reimplement once there is a more straight forward way to obtain pins from an integer coming from a variable or config file.