TSL: Add retroPassand example

[sunag]

Related issue: https://x.com/bruno_simon/status/2013640549761171724

Description

I ended up using @brunosimon's code to create a retro pipeline, also as a demonstration of how PassNode can manipulate materials. I also got some help from Claude with the post-processing effects, and it seems incredible how accurate the AI ​​was.

video-1770004216218.mp4

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	359.21 85.29	359.21 85.29	+0 B +0 B
WebGPU	618.49 172.18	618.3 172.12	-192 B -56 B
WebGPU Nodes	617.07 171.93	616.88 171.87	-192 B -55 B

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

	Before	After	Diff
WebGL	490.85 119.64	490.85 119.64	+0 B +0 B
WebGPU	692.07 187.26	692.12 187.28	+43 B +15 B
WebGPU Nodes	641.46 174.67	641.5 174.69	+43 B +15 B