Change server-side tutorial to use faucet

[mitschabaude]

• there is now an interact.ts script in the zk project template, which covers a subset of the tutorial (interacting with a deployed contract from the command line), in a cleaner and more robust way. the tutorial could start from this script and adapt it to add a custom deploy method.
• tx.wait() can replace the hacky loopUntilAccountExists()
• zkAppNeedsInitialization() can be left out, because this is handled automatically in SmartContract.deploy() now

EDIT: much of this is done with #234. The only "hack" that remains is loopUntilAccountExists(), our current API can't replace it as it is used in that example

[mitschabaude]

When the faucet function makes it into snarkyjs or the CLI, would be good to add that as well