fix(contracts): optimize gas usage in Attestation struct

[airope]

Summary

This PR addresses #918 by converting all Attestation struct instantiations from positional notation to named field {} notation.

Changes

• contracts/src/AttestationRegistry.sol: Updated attest() and massImport() functions to use named field notation for Attestation struct initialization
• contracts/src/stdlib/IndexerModuleV2.sol: Updated _buildAttestation() to use named field notation

Why

Using named field notation (Attestation({field: value, ...})) instead of positional arguments (Attestation(value, ...)) can save gas because the Solidity compiler handles struct packing more efficiently with named initialization. It also improves readability and reduces the risk of field ordering bugs.

Testing

No logic changes — only struct initialization syntax is modified. All field values remain identical.

---

Note

Low Risk
Low risk: changes only switch Attestation struct construction from positional to named-field syntax, with the same values assigned. Main risk is accidental field/value mismatch, but named initialization reduces that likelihood.

Overview
Switches Attestation struct construction to named-field initialization in AttestationRegistry.attest(), AttestationRegistry.massImport(), and IndexerModuleV2._buildAttestation().

This is a syntactic refactor intended to improve readability and potentially reduce gas, without changing the data written into stored attestations.

^{Written by Cursor Bugbot for commit 9dca6d7. This will update automatically on new commits. Configure here.}

[cla-assistant]

All committers have signed the CLA.