Light Wallet: Implement the mithril client WASM package in the explorer

[jpraynaud]

Why

We want to add the Mithril certificate verification in the explorer.

What

Use the Mithril client WASM to verify a certificate and its chain in the browser form the explorer. We have already made a first implementation in this PoC #1254

How

• Add a popup (or link to a new page) from the Certificate popup
• Compute automatically the genesis verification key from the url of the aggregator (by using the network code)
• Adapt the npm package publication (bundler or not, CI, ...)

Later

• How to cache the certificates already verified by the browser
• Handle abort of verify_certificate_chain function call.