shader demo

Signed in as __USERNAME__. Shader experiment sandbox, forked from seelie-app-sandbox: Odin + raylib compiled to WebAssembly via emscripten, rendered through the G-buffer + dynamic lighting pipeline (seelie_shader). The experiment: the world renders at the native 640×480, then a CRT present pass maps it onto the 2560×1440 canvas - aperture-grille triads, scanlines, phosphor bleed, and a convergence fringe (no curvature yet). Controls as in the sandbox: QWE/AD/ZSC or the left stick walk the 8 compass directions; Numpad +/− adjusts speed; the right stick or arrow keys override facing; [/] or D-pad cycles the character; the mouse wheel steps integer zoom, R resets; N toggles day/night, T the torch, U the tuning panel.