`CLAIM` note follow up tracking issue

[partylikeits1983]

The goal of this issue is to track the required follow up issues after #2188 is merged.

Required for immediate Gateway integration

• 1. Create high level helper functions for converting Solidity types into Miden Rust types. Related to Add conversion function for EVM address type (20 bytes) to AccountId #2229
• 2. Clean up inputs for create_claim_note()
• 3. Create a Gateway operator account that creates CLAIM notes

Personally I don't think 3 is needed, we can just use a BasicWallet account with NoAuth for the account that creates CLAIM notes.

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Not required for Gateway integration, but required for production bridge flow

• 1. Implement getLeaf() in MASM: Implement getLeafValue() in MASM #2220
• 2. Implement U256 -> Felt scaling down procedure (per spec/comment): Convert asset amounts between Miden and Ethereum #2011 (comment)
• 3. Implement _verifyLeaf() in MASM and tie it into mmr_frontier_keccak which @Fumuran is working on: Keccak-based MMR frontier (agglayer::collections::mmr_frontier_keccak) #2105
• 4. build_note_tag in MASM: feat: implement build_note_tag_for_local_account in masm #2235 (Blocked until feat: Refactor NoteTag to contain an arbitrary u32 #2219 is merged)
• 5. Refactor & clean up batch_pipe_double_words context: Add Agglayer CLAIM note & bridging in functionality #2188 (comment)
• 6. Add storage slot to agglayer faucet to store originTokenAddress context: Add Agglayer CLAIM note & bridging in functionality #2188 (comment)
• 7. Post-proof validation: verify leaf data (destinationNetwork for Miden, destinationAddress via faucet registry), compute GER = keccak(mainnetExitRoot || rollupExitRoot), and ensure the GER is stored in the bridge (temporary map of valid GERs) context: Add Agglayer CLAIM note & bridging in functionality #2188 (comment)
• 8. Refactor ClaimNoteParams context: Add Agglayer CLAIM note & bridging in functionality #2188 (comment)
• 9. Replace agglayer branch felts_to_bytes32 & bytes32_to_felts with packed_u32_elements_to_bytes and bytes_to_packed_u32_elements context: Add Agglayer CLAIM note & bridging in functionality #2188 (comment)

For 3, this is the Solidity _verifyLeaf() implementation: https://github.com/agglayer/agglayer-contracts/blob/e468f9b0967334403069aa650d9f1164b1731ebb/contracts/v2/PolygonZkEVMBridgeV2.sol#L908

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@bobbinth @mmagician - is there anything else needed to add to this list for immediate Gateway integration?

[mmagician]

3. Create a Gateway operator account that creates CLAIM notes [...] Personally I don't think 3 is needed

I also don't think this is needed - this should be handled by the agglayer-client that Gateway is building. The CLAIM note will be a pure "data-carrying-note" (i.e. not carry any assets) and so doesn't need any specialized account procedures AFAICS.

The rest of the items look 👍🏼

[mmagician]

One more item to eventually tackle: removing tag and serial number from OutputNoteData

[partylikeits1983]

removing tag and serial number from OutputNoteData

Would it make sense to make the P2ID output note's serial number be PROOF_DATA_KEY value since this is a hash of the underlying proof data?

[mmagician]

I think that would work!