!Currently broken!

This example is aimed to create a full-stack todo app with a built-in polkadot-based blockchain as a database. Such database can be easily customizable, contain logic written also in Rust, has strong consistency guarantees, easily replicable and optionally publicly verifiable. These features can be interesting for mission-critical data including finances etc. As of now even code copypasted from polkadot-sdk repo produces compilations errors and the amount of required apis for a minimal example is relatively huge so I've set it aside until things improve. Also, no real work on the client side has been done and subxt is probably the best option.