[Feature]: allow query tendermint block_results with gRPC

[xoac]

Summary

/block_results is available only via REST request but should be also available with gRPC.

Problem Definition

I need access to (begin, end) block events and tx's block events. For now I am using GetTxsEventRequest with request tx.height={}. Unfortunately there are some chains (for example osmosis) that are not backward compatible and query for block 3513 will fail with error "unable to resolve type URL /osmosis.gamm.v1beta1.MsgCreatePool: tx parse error: invalid request" (source).

block_results endpoint will be also usable for IBC relayers #11012

[alexanderbez]

So you want the gRPC layer to also proxy BlockResults too? At this point, we're starting to proxy almost every single CometBFT RPC method...

WDYT @tac0turtle?

[tac0turtle]

on the comet community call they talked about their data companion api and about exposing a grpc interface. This would allow us to stop wrapping things but also the data companion api would mean its not a node that has the rpc running. I guess we can wrap this for now.

[andynog]

This will be available in Comet v1
https://docs.cometbft.com/v1.0/explanation/data-companion/grpc

[tac0turtle]

we are opting to push this to the indexer level. There is a streamer there and we are wrapping up work on another that simplifies the overall system. In the effort to keep the feature set in the cosmos sdk smaller we are opting to not move forwards with this feature