nx_assemseq.nx

nx_assemseq.nx -- ASSEMBLY / DISASSEMBLY SEQUENCING from the STEP assembly tree (cadtwin P4b). Given the parsed as1 product structure (nx_step_parse: NAUO parent->child edges), compute a valid DISASSEMBLY ORDER: deepest parts (fasteners/leaves) come out first, the top assembly last -- a part is removable only after all its children are removed. = teardown/repair instructions for a flipped car, and the correct order for the /explodelab explode animation (explodelab already offsets by assembly depth = this order). Depth = longest path from the root (handles shared sub-assemblies). Verifies every edge: child removed BEFORE its parent. Composes nx_step_parse. Deterministic. LIB (no main; gated by nx_assemseq_gate). license_tier: ORIGINAL