Fix Sudoku and enable CLI to create init() proofs

[mitschabaude]

This PR

• fixes the sudoku example
• does a fairly large refactor of the sudoku example, so that it doesn't rely on this.sign(), uses Struct instead of CircuitValue, uses snarkyjs APIs directly instead of custom helper functions, and makes run.ts script use proofs (the tests use proofsEnabled: false)
• during deployment, checks if the smart contract has init() decorated with @method. If yes, then we have to create a proof to deploy successfully; this is done in a separate step that's shown to the user, after building the transaction

Other small changes:

• Add TS config at the top level so we have proper type feedback in the examples
• Tweak eslint config to not show an error for the sudoku code

[ymekuria]

I think this will will be easier for people to follow without the helper methods. I just had some minor comments but everything looks good.