The transparency log component listens for (new) blocks and indexes transactions

[erwin1]

Using the add listener API from the blockchain component, the transparency log component listens for blocks and indexes all transaction payloads in its transaction payload index component (#680)

[betarelease]

can you check on the progress of this one as well @tiainen @johanvos ?

[tiainen]

I believe this is pending the work that is done in #893. @fishseabowl can probably confirm?

[fishseabowl]

Transparency log service can register related APIs with the blockchain service through the blockchain::add_payload_listener method in #893.