Add reference type ID to MessageOut receipt

[ra0x3]

Issue

• The Fuel Indexer allows users to index a MessageOut receipt
• This MessageOut receipt is important -- one of the most important receipts -- because the messages are bridge messages
• This receipt includes a hexadecimal payload field data that contains the byte payload sent in the receipt
• Currently, we (using the indexer) have no way of deserializing that data payload into some type of struct/object
• The LogData receipt works a bit similarly in that it also has a data payload that can be deserialized
• However, the difference between LogData and MessageOut is that LogData includes a reference type ID -- that allows us to know which entity/object to deserialize the data payload to

Recommended Solution

• We should add some reference type ID to the MessageOut receipt, so that users know which type the MessageOut data payload will deserialize to
• @adlerjohn Suggested merely appending the 64-bit reference type ID to the beginning of the MessageOut data payload in the stdlib

CC @nfurfaro because this might involve stdlib
CC @mohammadfawaz because this is Sway-related
CC @deekerno

[ra0x3]

• There seems to be a somewhat related issue here Adjustments to send_message() #3401
  • This ☝️ seems to have reached a resolution - with @mohammadfawaz suggesting we don't have a register to keep track of the reference type ID
    • However, the solution suggested by John (for this issue Add reference type ID to MessageOut receipt #3409) asks if we can just prefix the data payload with the type ID

[ra0x3]

@mohammadfawaz Just following up on this :)

[mohammadfawaz]

I believe this can be closed now after #3564