Ah, got it working on tortoiseSVN at least. Right clicked on my working directory, chose relocate... and gave it "svn+ssh://roippi@svn.code.sf.net/p/kolmafia/code".
The sourceforge page points you to http://svn.code.sf.net/p/kolmafia/code/trunk, but that's a completely bogus address. Dropping the /trunk off the end does get you to a read-only version of the repo.
It looks like https://sourceforge.net/p/kolmafia/code/HEAD/log/ can be used to look at the most recent changes, but it takes a long time to load (around 15 seconds). https://sourceforge.net/p/kolmafia/code/HEAD/ lets you view the entire commit message, though for the RSS bot you might want to replace HEAD with the version number that comes after whatever you last parsed and keep going to the next version if there's a link on the page for it. There's also https://sourceforge.net/p/kolmafia/code/feed but it seems to update slowly.
Apparently the RSS Bot got stuck again... updates 11871-11875 haven't shown up yet, despite being visible when you look at Daily Builds.
Very sorry, I am an idiot
SVN Tracker link should probably point to https://sourceforge.net/p/kolmafia/code/HEAD/tree/ now.
So, the default (for whatever reason) diff is the "unified" view, but I find the side-by-side view to be massively better. If others agree, adding a &diformat=sidebyside field to the diff links could save a click.