Function tx_type_has_poster_costs 

pub fn tx_type_has_poster_costs(tx_type: u8) -> bool

Whether a transaction type incurs L1 poster costs. Only standard EOA-signed tx types (Legacy / EIP-2930 / EIP-1559) pay; all Arbitrum-specific types (deposit, unsigned, contract, retry, submit-retryable, internal) skip L1 charging.