Websocket ingress identification in Dashboard

[tkurki]

For ws connections that send data to the server the dashboard shows delta statistics, just like for connections configured explicitly at the server. One fundamental difference is that the server's connections have an explicit id, while ws connections are now identified by either

• clientId originally provided by ws client in access request (security on), essentially a random string, prefixed with ws.
• just the string wsws on a server with security off - and with a single line showing total for all ws clients that produce data
• probably not used much, but the username of an authenticated ws connection, not originated from an access request, prefixed with ws.

This is pretty confusing and not very useful: the user sees just random uuids from for example SensESP sensors.

Instead we could show a separate line for each ws connection that is producing data. If the connection is authenticated with a token originating from an access request we either show the description included in the original access request inline / on hover and / or provide a link to the device in the Devices page.

https://github.com/SignalK/SensESP/blob/0b6b067c498e4389bd0db82308c7b080d6c19f83/src/net/ws_client.cpp#L365-L372

Current deltastatistics implementation never evicts anything. If we do this a ws connection's statistics should be removed on disconnect.

[mairas]

SensESP devices send the configured device hostname as the "label" field of the SK Delta. I wonder would it be feasible to use that as the delta source, in the format of ws.hostname?

[tonybentley]

@tkurki i have a draft PR for this issue. I need to do a little more testing with a device setup using mdns then I will send to review. Feel free to take a look and comment on what I have if you want to get a head start