WASM modules should not be stored as Base64

[KOLANICH]

• OpenCV => https://docs.opencv.org/5.x/opencv.js
• Operating System / Platform => JS + WASM
• Compiler => Emscripten

Detailed description

Base64 is bloat.

Steps to reproduce

1. Download https://docs.opencv.org/5.x/opencv.js
2. Open in a text editor
3. See base-64 encoded WASM module.

Issue submission checklist

• I report the issue, it's not a question
• I checked the problem with documentation, FAQ, open issues,
  forum.opencv.org, Stack Overflow, etc and have not found any solution
• I updated to the latest OpenCV version and the issue is still there
• There is reproducer and related data files: videos, images, onnx, etc

[asmorkalov]

It looks like base64 comes from this line (-s SINGLE_FILE=1): https://github.com/opencv/opencv/blob/4.x/modules/js/CMakeLists.txt#L73

[KOLANICH]

Thanks.