Do profiling of the sitemap

[plexus]

The sitemap xml takes a looong time to load. We should at least get to an understanding of where that time is spent.

Can we query more efficiently?

Is the XML rendering slow?

Can we grab the data from the indexer component instead? -> I'm pretty sure we have the necessary data already here in memory, so if the querying is the bottleneck then this would make a big difference.

It's also worth looking at the cloudflare settings, I have the impression this isn't being cached, even though it should be very cacheable.