ServerConfig assumed that the state was already correct when
checking the given urls against the default, but that is not
neccessarily the case (eg. the validation can return a different
url to what the user entered). This would cause an infinite loop
because it would keep firing onServerConfigChange to change to
the desired URLs but the state would never change.
Fixes part of https://github.com/vector-im/riot-web/issues/10666
This hides the identity server at first from the custom server auth flows. For
the flows that may need an IS if the HS requires it (registration, password
reset), we then check with the HS before proceeding further and reveal the IS
field if it is in fact needed.
Fixes https://github.com/vector-im/riot-web/issues/10553
This performs liveliness checks on the auth pages to try and show a friendlier error. Earlier checks in the app startup are expected to not block the app from loading on such failures.
See https://github.com/vector-im/riot-web/issues/9828
