Add PADO to Linea doc in Tooling & Infra section

[xiafubiao]

Hello Team,

I'd like to propose adding a section on the PADO project within "Build on Linea > Tooling and Infrastructure > Attestation". PADO is a cryptography-based infrastructure to bring all Internet data into smart contracts. To be more precise, PADO leverages interactive ZK and MPC techniques to "blindly" validate Internet data via TLS channels. Such techniques can be roughly viewed as “private oracles” that retrieve users’ private data from Internet sources, compared with public oracles that feed public web data to smart contracts. In addition, the Internet data is reliable because the data authenticity is guaranteed under the ZK-based attestation pipeline, and the privacy is well protected regarding to specific application logic by using zero-knowledge proofs.

We would like to propose PADO as a type of attestation protocol, rather than oracles, because we think the former is a more broader expression considering the scenarios of the protocol outputs.

PADO dApp is developed on Linea, and integrated with Verax attestation registry. Users can create their own Internet data attestations by using PADO dApp. These attestations can be stored and accessed from Verax by all Linea dApps.

Introducing PADO section in the documentation gives general guidance on how users or developers can create and use off-chain data attestations in various scenarios.

I'll create a PR for this section. Feedback and thoughts are welcome!