Fix transaction summary with contract calls

[danielbate]

The current implementation of the transaction summary uses the param1 property from a contract call receipt to build out the contract element of the summary.

As recently deduced, param1 no longer represents the encoded function selector. Likewise, param2 does not represent the encoded function arguments. They now represent pointers to their respective data.

Therefore currently the only way to deduce the function selector from a transaction is to decode it from the scriptData that was passed on the transaction, as documented here. This is because scriptData, when used with contracts, represents the entire contract call script.

Therefore we need to:

• Fix the transaction summary to properly display contract call info
• Add more test cases for contract calls in the transaction summary
• Check all references to param1 in the SDK and confirm they are not being misused

Reference:

• Is the "param1" of the call receipt no longer the function selector on the testnet? #2424

[danielbate]

I actually think this may be linked to #2448