Add spend note transaction builder

[ross-weir]

Spending a note:

In note Context vars: 0: 0 byte (>= 0 means spend, also encodes note output index in outputs, which allows multiple note spends in single tx) 1: GroupElement, a of signature 2: ByteArray, z of signature 3: ByteArray, avltree insert proof

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Out note

• R4 - avltree with inserted reserveNftId -> signature
• R5 - next holders pk as GE (current holder of note)
• R6 - Increment +1 (length of signers)

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Transaction structure Inputs: n: note in

Outputs: n: note out

Data inputs: 0: reserve box that holds the nft that was inserted into avltree of out note

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Store Will likely need to add a SignerService to the store that has a method like signers().restore_prover(&note): BatchAVLProver in order to sign the note and insert values. Or maybe makes sense to have it on notes like notes().restore_prover(note_id)

[kushti]

Hello. kushti I am a dev who is interested in your issue Could you give me a chance to work with you?

Sure, assigned you. Any help needed ?