I chose the most common one here, although the indentation is a bit odd.

types.h:
Remove the definition of `jack_native_thread_t` as we will be relying on
the one from systemdeps.h.

{jack,thread}.h:
Include systemdeps.h for definition of `jack_native_thread_t`.

jack_port_get_latency_range only returns meaningful values after ports get
connected, and that is signalled via the latency callback. Saying that it's
normally used in callbacks is too soft, the docs should make it clear that the
function is not very useful outside of the callback, because you don't know
whether the port is connected / whether the latency values changed.

Somebody forgot to change the copy/pasted comment...

This is semantically similar to jack_port_set_name() but because it is also passed a jack_client_t*, it can
contact the server to ensure that not only the rename is done but that port rename callbacks are delivered
appropriately