sequencer-client: add extension trait to subscriber to new sequencer …

…blocks (#382)

## Summary
Add a `SequencerSubscriptionClientExt` trait with a
`subscribe_new_block_data` method.

## Background
Removing gossipnet from conductor as part of
#332 requires it to read new
blocks directly from cometbft / sequencer. This patch extends the
sequencer-client crate to provide that functionality using a convenience
function so that conductor need not know how to convert comertbft
new-block events to sequencer block data.

## Changes
- Add a `SequencerSubscriptionClientExt` trait to the sequencer-client
crate.
- Reorganize the sequencer-client crate to export items under the
appropriate features.
- warn users if they set neither the `http` nor `websocket` features.

## Testing
Testing this client is out of scope for this PR. We are relying on the
underlying tendermint-rpc WebSocketClient being correctly implemented.
It would be great to extend wiremock or a similar crate to provide a quick way
to test websocket APIs.

An alternative is to derive a jsonrpc server with jsonrpsee, but that's
a lot more work.

## Breaking Changelist
None, only functionality was added crates depending on sequencer-client
were not touched.

## Related Issues
Part of #332

#375 and
#376 are precursor PRs
unblocking this patch.

---------

Co-authored-by: noot <36753753+noot@users.noreply.github.com>

Cargo.toml

@@ -62,6 +62,7 @@ tendermint = "0.32"
 tendermint-config = "0.32"
 tendermint-proto = "0.32"
 tendermint-rpc = "0.32"
+thiserror = "1"
 tokio = "1.28"
 tonic = "0.9"
 tracing = "0.1"

crates/astria-sequencer-client/Cargo.toml

@@ -5,12 +5,15 @@ edition = "2021"
 
 [dependencies]
 proto = { package = "astria-proto", path = "../astria-proto" }
+sequencer-types = { package = "astria-sequencer-types", path = "../astria-sequencer-types" }
 
 async-trait = { workspace = true }
-eyre = { workspace = true }
+futures = { workspace = true }
 hex = { workspace = true }
 tendermint = { workspace = true }
 tendermint-rpc = { workspace = true }
+tracing = { workspace = true }
+thiserror = { workspace = true }
 
 [features]
 http = ["tendermint-rpc/http-client"]