Allow gRPC clients codegen

[dimazhornyk]

Hey! As gRPC is the main protocol used by Celestia, you need a client code to be generated for a .proto definitions (something like this).

The only way to achieve it now is to store all the proto files in any Celestia client implementation, which is a bit unnecessary, especially taking into account that you have a great celestia-proto package that could cover that.

Here is how it is done in Astria's codebase, it would be great if there was an opportunity to do something similar with celestia-proto using a feature flag. It doesn't necessarily have to be tonic and tonic_build, but those are kind of standard, so using them makes the most sense.

Also, here is the minimal list of methods required for a client, I don't remember which exactly, but some of the files weren't included in the list that you compile here:

use super::{
    celestia_proto::{
        query_client::QueryClient as BlobQueryClient, MsgPayForBlobs,
        QueryParamsRequest as QueryBlobParamsRequest,
    },
    cosmos::{
        auth::{
            query_client::QueryClient as AuthQueryClient, BaseAccount, QueryAccountRequest,
            QueryParamsRequest as QueryAuthParamsRequest,
        },
        base::{
            node::{
                service_client::ServiceClient as MinGasPriceClient,
                ConfigRequest as MinGasPriceRequest,
            },
            v1beta1::Coin,
        },
        crypto::secp256k1,
        tx::v1beta1::{
            mode_info::{Single, Sum},
            service_client::ServiceClient as TxClient,
            AuthInfo, BroadcastMode, BroadcastTxRequest, Fee, GetTxRequest, ModeInfo, SignDoc,
            SignerInfo, Tx, TxBody,
        },
    },
    tendermint::types::{Blob as PbBlob, BlobTx},
};