Few fixes to retriever server

[ian-shim]

Why are these changes needed?

• more readable logs in retrieval client
• retriever server loads G2 points for verification
• the onchain call to get logs takes from/to blocks so the call can be made with tighter block range

Checks

• I've made sure the lint is passing in this PR.
• I've made sure the tests are passing. Note that there might be a few flaky tests, in that case, please comment that they are not relevant.
• Testing Strategy
  • Unit tests
  • Integration tests
  • This PR is not tested :(