nx_world_shader_cumulus_canonical_t156.nx

nx_world_shader_src.nx -- THE WORLD SHADER, WRITTEN ONCE (gameengine GE44 R-G, 2026-09-04). The voxel world pass that nx_game_page_emit ships hand-written twice (a GLSL FSH for the WebGL2 door and a WGSL module for the WebGPU door) is authored here ONCE as shader-IR builder calls and emitted to BOTH dialects by nx_wgsl. Every function below is the hand WGSL, statement for statement (vx, h21, h31, pal9, sky, struct Hit, march, shade, the fragment entry); the vertex entry is the backend's own fullscreen triangle (shsrc_fullscreen_tri). Deliberate deltas from the hand text, all semantic no-ops: compound assignments are spelled x=(x+y); unsigned constants are casts (u32(0) / uint(0)) because the GLSL backend spells a u32 literal without its suffix and a bare 0 beside a uint is a GLSL type error; the WebGPU top-left fragment origin is carried as the uniform `yflip` (1 on the WebGPU door, 0 on WebGL2) instead of a per-dialect edit, so ONE source serves both doors. The uniform block is declared ONCE here (ws_world_uniforms) and `nx_wgsl layout` derives its memory layout from it. GE55 (2026-09-05): the world module now takes the sim's RAW state words as its uniform block (ws_world_uniforms_raw, the same 40-word table as nx_wasm_craft UR_*) and derives every float in upk() into module-scope private state, so the page packs nothing and computes nothing; ws_world_uniforms (the f32 block) stays as the R-F layout ruler fixture. license_tier: ORIGINAL