feat(berachain): light client (#1963)

berachain light client + full voyager support, confirmed to be working
on testnet:
https://bartio.beratrail.io/address/0x4e86d3Eb0f4D8DDcCEC2B8fA5cCFC8170e8ac3dC.
the client itself is basically a copy-paste of the tendermint client,
with some eth verification shoved in.

- add `cometbft-rpc`
- use `pbjson_types` instead of generating the well known protobuf types
so that they correctly implement their json mapping
  - some very hacky proto generation, don't worry about it