Edge shader now takes u_edge_color and u_edge_opacity uniforms.
Grid section added to sidebar with a color picker and opacity slider.
Blending enabled around edge draw call to support sub-1 opacity.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Maze overlay and wall shaders removed per review feedback.
build_goldberg_adjacency moved from maze.mjs into topology.mjs
where it belongs — it is pure face-graph topology used by paint tools.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>