Add a function to run tweaks in the mock chain

[carlhammann]

This clarifies the documentation comment for runTweakInChain and adds a function

runTweakInChain' :: MonadBlockChainWithoutValidation m => Tweak m a -> TxSkel -> m [(a, TxSkel)]

which allows one to manually apply a tweak to a transaction, returning all modified transactions in a list.

@gabrielhdt and I discussed something like this in the morning, and because I'm not convinced that this feature is useful in the spirit of much of the rest of cooked, at least MonadModalBlockChain, I thought I'd open this PR to discuss it with you.

[carlhammann]

Perhaps you can deprecate the function, to go one step further?

As it stands, the implementation of MonadModal for the staged monad relies on runTweakInChain, and the reason why is quite interesting: If we were to abandon runTweakInChain :: MonadPlus m => ... -> m (a, TxSkel) in favour of runTweakInChain' :: ... -> m [(a, TxSkel)], that would mean that we'd have to replace everything starting at this line by something like

modifedSkels <- runTweakInChain' now skel
msum $
  map (\(_, skel') -> do
        lift $
          lift $
            tell
              [ MCLogSubmittedTxSkel
                  (SkelContext managedTxOuts managedDatums)
                  skel'
              ]
        tx <- validateTxSkel skel'
        lift $
          lift $
            tell
              [MCLogNewTx (Ledger.getCardanoTxId tx)]
        put later
        return tx
  )
  modifiedSkels

The difference is that, in the version we currently have, if one result of the tweak fails with a fail or throwError, the other results will still be tried. In the other version, if one alternative fails, no modified transaction is tried.