Internet connection status should be non-binary

[Williangalvani]

we should have a value for "limited connectivity" where some pings go through and some don't.
We shouldn't limit functionality unless we are 100% we are offline

[ES-Alexander]

Marking this as important because not every pinged address is required for every internet-connected service. Services should only be disabled when their relevant domain(s) cannot be connected to¹, and that information is already provided in the underlying internet check.

It would also be helpful to include a limited connectivity icon (e.g. mdi-web-minus) in the status bar, and allow clicking on it to see a summary of which pings domains are failing to respond (and ideally which services cannot be used as a result).

Footnotes

1. As extra context, a ping can be blocked because a site is down, or because the user or their ISP have intentionally blocked it, and us blocking unrelated functionality when that's the case may come across as problematic. ↩