nx_texm_ship_gate.nx

nx_texm_ship_gate.nx -- THE GATE FOR THE DERIVED SHIP RESOLUTION. SUBJECT: the nx_nxa_texm ELF, ship mode, forked for real. tex_res_floor stays the MEASURED bar; ship mode DERIVES the largest power-of-two rung whose measured bytes*cast_size fit a declared texture budget, and REFUSES when the budget is unsourced/absent or nothing fits. This gate proves the derivation RESPONDS to its inputs (budget and cast size) and abstains when it cannot decide -- never silently defaulting. EVERY BUDGET FIXTURE IS WRITTEN AT RUNTIME under /tmp/nx_texm_ship_gate/ and passed to the organ via its conf-path OVERRIDE (4th arg), so the gate never mutates the tracked production budget conf -- a gate that shares a fixture with a production conf reports on the fixture. The override arg exists precisely so this test is clean. ALL FIXTURES SELECT 512 OR REFUSE, ON PURPOSE: a 512 bake is fast and a refusal skips the bake entirely, so the gate finishes inside any caller deadline. A budget that selected 2048/4096 would derive correctly but bake slowly -- correctness is proven by the 512 case plus the discrimination pairs, not by paying for a large bake. license_tier: ORIGINAL No hw writes (Rule 26). expect_exit: 0