Network faucet

This is an exploratory issue to discuss the potential effects of a network faucet.

A network faucet would require the client to submit transactions with a mint note and the network account would handle them. So, essentially, there is no need to run a backend service with the faucet account generating transactions. There would not be any PoW, rather the fees would avoid spamming.

Since the network faucet requires the users to generate the network transaction by themselves, the frontend would change. It would be in charge of building the transaction with the mint note and then use the wallet-adaptor API (the `requestTransaction` method) to submit it. This network faucet would require users to have the wallet installed.

Additionally, the faucet CLI could also handle the network account deployment and allow for later modifications on the deployed account.