Fixes and improvements for v2.0-rc11

[tve]

Priority:

• display wifi state using rPi green LED
• add charts to radio tab to support noise measurements
• improve set-up of hotspot password when using raspi-imager
• support hotspot-less install via SGhub link
• split detections (lotek/ctt) and per-antenna on SGhub
• improve update/upgrade process UI (needs better feedback)
• improve bulk deployment process (input welcome!)
• turn hotspot off automatically, offer "off", "on", "20m@boot"?
• add monitoring of tags detected to SG Hub
• show USB/radio ports timeline in SG web ui
• show reboot timeline in SG web ui

Desirable:

• upgrade to node.js v18
• rework GPSd start-up and configuration
• fix uninitialized clock issues when using raspi-imager set-up
• improve sg-control install (avoid compilation of pam module)
• do not print connectivity check failure every time (2 lines!)
• remove session id in HTTP auth for FlexDash
• Adafruit GPS seems to show "no-dev" right after boot until is gets a fix
• Display which software track the SG is on (stable vs testing) and provide toggle
• add more help info to widgets in the web interface
• fix formatting of widget info
• add monitoring of upload errors (is what's there enough?)
• start data files with radio freq
• start data files with some random stuff or SG-ID (remember why?)
• captive portal browser on MacOS doesn't show plots or allow download, safari works fine
• show ports for radios on timeline plot
• add "data cap" (idea needs fleshing out)
• When configuring Client WiFi from hotspot, add warning that hotspot will briefly turn off.
• avoid shipping dup log file at midnight
• add button to perform connectivity check