I've searched through the 250(ish) books that form the Star Wars EU and I can find no reference to the terms "Claytronics", "Programmable matter" or "Catoms".
There are some slight glancing references to nanotech in various Elizabeth Hand novels ("Hunted", "A New Threat", "Pursuit"), "Rule of Two" by Drew Karpyshyn "The Swarm War" and "The Unseen Queen" by Troy Denning and "Hard Contact" and "True Colours" by Karen Traviss.
Nanotechnology seems to mainly find use in slavery devices, bio-weaponry (nanoviruses), illegal medical devices, biological computing and forced terraforming. Whenever it's mentioned in the EU canon, there seems to be an underlying sense of wrongness either because it's a very alien form of technology (e.g. almost exclusively used outside the core worlds of the Galactic Republic) or because of the grey goo threat.