Function confirm_and_build 

pub(super) async fn confirm_and_build<'a, N: Network, P: Provider<N>>(
    builder: CastTxBuilder<N, P, InputState>,
    sender: impl Into<SenderKind<'a>>,
    force: bool,
    lane: Option<&ResolvedLane>,
    rpc_signs: bool,
) -> Result<Option<N::TransactionRequest>>
where
    N::TransactionRequest: FoundryTransactionBuilder<N>,

Confirms the authorization disclosure, builds the transaction for sender and prints the resolved lane. rpc_signs marks modes where the RPC signs the transaction, which discloses every authorization regardless of how the request is filled.

Returns None when the user declined.