Development statistics for 6.13

The 6.13 development cycle ended on January 19 with the release
of the 6.13 kernel. This cycle was, on its surface, one of the slowest we
have seen in some time; the LWN merge-window summaries (part 1, part 2) and the KernelNewbies 6.13 page
can be consulted for a refresher on all it contains. Here, instead, we
will take our usual look at where all of those changes came from.