Add a new tutorial from web app ui starter (vite framework)

[antho31]

Step-by-step tutorial on how to build a web app on top of the OKP4 blockchain.

Vite project with pieces of code to show how to connect a wallet to the OKP4 testnet, interact with smart contracts, decode transactions

From https://github.com/okp4/web-ui-boilerplates

[fredericvilcot]

@antho31 @ccamel This PR is linked to the web app boilerplate, that is a private repository with code that must be first improved and then validated by product team / web team. So, I am not confortable with the idea to publish this work on the whitepaper for now.

[antho31]

Thanks @ErikssonJoakim for your feedback 🙏