Improve Unused arguments rule

[fcasal]

Currently, the rule finds unused function arguments. However, Cairo programs commonly use the pattern:

struct BatchConfig:
    member general_config : GeneralConfig*
    member signed_min_oracle_prices : OraclePrice*
    member signed_max_oracle_prices : OraclePrice*
    member n_oracle_prices : felt
    member min_expiration_timestamp : felt
end

func batch_config_new(
        general_config : GeneralConfig*, signed_min_oracle_prices : OraclePrice*,
        signed_max_oracle_prices : OraclePrice*, n_oracle_prices, min_expiration_timestamp) -> (
        batch_config : BatchConfig*):
    let (fp_val, pc_val) = get_fp_and_pc()
    return (batch_config=cast(fp_val - 2 - BatchConfig.SIZE, BatchConfig*))
end

https://github.com/starkware-libs/stark-perpetual/blob/9327c640e59bd15764833505560478d33aa6a8b1/src/services/perpetual/cairo/transactions/batch_config.cairo#L1-L19

We need to

• check the usage of cast(fp_val - 2 - STRUCT.SIZE, STRUCT*)
• check that all struct members and function parameters match in number and type