Image assets in this folder are loaded by `manifest.json`.

Add new browser-friendly image files here, then add each filename to the
manifest's `files` array. The demo crops or scales them into the 320 x 160 main
effect area. Main-demo ordering is controlled by `src/demoSequence.ts`, where
public image cues reference these files by name.

The secret tracker also reads this manifest for random 320 x 200 backdrops. It
uses browser-friendly still image formats for that backdrop pass.
