North Korea is continuing to expand its nuclear arsenal and missile capabilities, including efforts to field more advanced and survivable systems, according to a new Congressional Research Service (CRS) report. The Oct. 13 CRS update says Pyongyang is pursuing a broader range of nuclear-capable delivery systems while expanding production of the fissile material needed to build additional warheads. The report also highlights a growing focus on solid-fueled missiles, hypersonic weapons and multiple-warhead technologies. The assessment comes as North Korea has…