nx_jam_detect.nx

nx_jam_detect.nx -- SOVEREIGN clog/jam detector (QIDI fix; complements nx_print_runtime_monitor's spaghetti/temp/shift detection, which does NOT cover a feed-side JAM). Researcher-grounded (nx_research over FFF): "compressive stress IS THE driving force behind extrusion" -> a JAM = that chain broken: the extruder COMMANDS filament advance but little/none actually FEEDS (heat-creep softening above the melt zone, PTFE-heatbreak gap, partial clog, or gear grinding). Stock QIDI has only a binary runout sensor; this uses a filament-MOTION signal (commanded-E vs measured-feed, e.g. a BTT Smart Filament Sensor encoder) to catch jams EARLY, before a long print is wasted -- predictive, sovereign, cheap. license_tier: ORIGINAL.