Leios's Voting Demo

[hjeljeli32]

Description of the changes:
This PR adds a Demo that illustrates the Leios voting and certification flow.
It includes helper scripts that invoke the existing Rust CLI implementation to generate inputs and results, along with a browser-based UI for visualization.

Purpose:
Provide an end-to-end visualization of the Leios voting and certification mechanisms.

Main components:

• scripts/ — Bash scripts that call the Rust CLI to run the voting workflow.
• templates/index.html — HTML structure for the demo interface.
• static/app.js — Handles dynamic visualization of the CLI outputs.
• static/styles.css — Provides layout and color styling for clarity.

Related issue:
Closes #564

Reviewers:
@ch1bo @bwbush
(Please let me know if you think others should also review this PR.)

[ch1bo]

Works and I got some good timing results :)

[ch1bo]

The workflow works fine once set up. Further improvements are of course possible, but this is good stuff already!

[ch1bo]

The scripts were a bit annoying to run for me:

• I was using PATH to point to the binary at first (as required on line 9)
• Then I learned that CLI needs to be set, which I did
• Then I saw that scripts/.env_cli needs to exist
• Which had me look at 00_set_cli.sh script, but that did not accept the binary in my ase

I would suggest to lower the specific requirements and just expec the leios_crypto_benchmarks on the PATH, or be explicit about needing CLI to be set.

FWIW I was using direnv and a nix-shell to get the binaries and python packages in place, but this is different for each user.

[hjeljeli32]

Thanks a lot for the feedback, @ch1bo — and apologies for the confusion with the README setup instructions.
I reviewed the steps and have now created a PR that updates the README with corrected and simplified instructions for running the demo.

Because my laptop currently has limited disk space, I wasn’t able to use Nix for this setup — so I focused on making sure the demo can also be run easily without it.

Here’s the PR with the fixes:
👉 #606