Auto Configuration of Home Assistant Cloud ICE

[RyanMorash]

Home Assistant added an API in 2025.12 that can fetch the HA Cloud ICE servers and credentials: home-assistant/core#157774

It would be nice if Frigate would allow us to use a long-lived access token to retrieve that information and automatically configure go2rtc.

[NickM-27]

go2rtc already supports receiving and using a users Home Assistant config, so I would expect that it would make sense for go2rtc to be able to do this. I don't believe we'd want to add more dependency on specific HA features that could change / be a breaking change in the future.