Apple dropped support for some older platforms, so we can also remove
the annotations for them.
See https://developer.apple.com/support/xcode/ for the supported
versions.
This patch adds a large number of missing includes in the libc++ headers
and the test suite. Those were found as part of the effort to move
towards a mostly monolithic top-level std module.
When I implemented `condition_variable_any::wait`, I missed the most
important paragraph in the spec:
> The following wait functions will be notified when there is a stop
request on the passed stop_token.
> In that case the functions return immediately, returning false if the
predicate evaluates to false.
From
https://eel.is/c++draft/thread.condition#thread.condvarany.intwait-1.
Fixes#76807
