Improve logging for indexer models and processors

[dermanyang]

Purpose

Context for onboarding task

Additional metadata (write_set_change_index and/or txn_version) to logs for easier debugging. Namely, logs in

• coin_utils.rs
• write_set_changes.rs
• ans_processor.rs The rest of the diff is just making the appropriate variables available for the logging.

Testing

Ran default_processor (for wsc.unspecified logging), ans_processor and fungible_asset_processor locally.