This allows us parsing which kind of script the user wants to query, and the associated payload, like a hash or pubkey.
We currently only support P2PKH, P2SH and P2PK, as these are the only ones widely used. Other types of scripts can be queried using the Other script type.
There's no OP_RETURN variant, as we don't index the tx history nor the UTXOs of OP_RETURN scripts.
Depends on D13531.