improve symbolic byte handling in traces

[karmacoma-eth]

When we generate calls with symbolic calldata, the trace output is not great. For example, in Unstoppable, we have this straightforward Attacker code:

contract SymbolicAttacker is Test, SymTest {
    function attack() public {
        address target = svm.createAddress("target");
        bytes memory data = svm.createBytes(100, 'data');
        target.call(data);
    }
}

But when we run halmos --function check_unstoppable --solver-timeout-assertion 0 -vvv --statistics, we get this inscrutable part of the trace:

        CALL SymbolicAttacker::attack()
            STATICCALL svm::0x00000000(Concat(0x0000000000000000, halmos_target_address_d261631_01(), 0x0000002000000000000000000000000000000000000000000000000000000000000000067461726765740000000000000000000000000000000000000000000000000000))
            ↩ Concat(0x000000000000000000000000, halmos_target_address_d261631_01())
            STATICCALL hevm::assume(If(==(halmos_target_address_d261631_01(), 0x00000000000000000000000000000000aaaa0005), 0x0000000000000000000000000000000000000000000000000000000000000000, 0x0000000000000000000000000000000000000000000000000000000000000001))
            ↩ 0x
            STATICCALL svm::createBytes(0x0000000000000000000000000000000000000000000000000000000000000064000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000046461746100000000000000000000000000000000000000000000000000000000)
            ↩ Concat(0x00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000064, halmos_data_bytes_db9a296_02())
            CALL 0xaaaa0002::Extract(halmos_data_bytes_db9a296_02())(Extract(halmos_data_bytes_db9a296_02()))
                LOG3(topic0=Transfer, topic1=0x00000000000000000000000000000000000000000000000000000000aaaa0005, topic2=Concat(0x000000000000000000000000, Extract(halmos_data_bytes_db9a296_02())), data=Extract(halmos_data_bytes_db9a296_02()))
            ↩ RETURN 0x0000000000000000000000000000000000000000000000000000000000000001
        ↩ STOP 0x