pub(crate) fn move_tx_to_execute_pointer(&mut self) -> usize {
        assert!(
            self.tx_to_execute < self.free_tx_index(),
            "Attempt to execute tx that was not pushed to memory. Tx ID: {}, txs in bootloader: {}",
            self.tx_to_execute,
            self.free_tx_index()
        );

        let old = self.tx_to_execute;
        self.tx_to_execute += 1;
        old
    }
Returns the ID of the next transaction to be executed and increments the local transaction counter.
core/lib/multivm/src/versions/vm_boojum_integration/bootloader_state/state.rs