ABI-less Decoding of Calls + Event

[sourabhniyogi]

This PR contains new BigQuery UDFs to decode EVM calls and events without knowing an ABI using 2 key functions:

• abi_functions.PARSE_CALL(input)
• abi_functions.PARSE_EVENT(data, topics)

To support ABI-less decoding, each of the above function uses a large ~1MB library containing 2 compressed maps, one covering known call methods and known event topics. Using the call 4byte methodID or the event's topic[0], the most likely ABI is synthesized from the map and decoding is attempted. For events, given the number of topics observed and the ABI guess, any mismatch results in combinatorial search on all possible indexed combinations, with the first success considered valid.

How It Works:

• Big Picture: approach taken in PARSE_CALL and PARSE_EVENT is to build a 1MB library of 2 compressed maps: call_map and event_map
• A signatures table is compiled by aggregating ABI signatures with 2.8MM+ records from multiple open-source repos. However most of these hex signatures have never bee observed on chain.
• So, we tally actual observations (numObservations from logs and transactions) and presence in ABI contracts (numContracts from contracts) in crypto_ethereum.{ EVM Chains to build a reduced dataset

[allenday]

Hi @sourabhniyogi, I've requested that the referenced JS files be added to a GCP-owned bucket.

I'll merge the PR after we're able to get them added to the new location and update the diff here.

Thanks.