Consider polytope-labs/sync-committee-rs for preprocessing

[nulltea]

Analogous to https://github.com/ChainSafe/Banshee/issues/47, but instead of the entire beacon state, we only need light client sync committee data and block roots. There, the blocker was in the lack of specific SSZ methods in ssz-rs; we don't need those methods, so the option of writing data retrieval and pre-processing in Rust is relevant again.

The potential shortcut could be by using https://github.com/polytope-labs/sync-committee-rs.

Scope:

• try applying polytope-labs/sync-committee-rs to retrieval data in form of SyncState
• as a reference, see its mock generation in https://github.com/ChainSafe/Spectre/blob/main/preprocessor/scripts/generateInputData.ts#L120
• disregard merkle_trace field

[araskachoi]

for the link that you posted, it still looks like it's using "mock data" where the script is generating data (primarily for private keys and validators). the script would also require calling to an exposed endpoint and retrieving the beacon state for a light client?

[nulltea]

The goal is to use Rust for data retrieval and pre-processing and hopefully to re-use methods from polytope-labs/sync-committee-rs