feat: introduce new kafka topic consumer respecting WAL index

src/log-store/Cargo.toml

@@ -26,7 +26,9 @@ common-time.workspace = true
 common-wal.workspace = true
 futures.workspace = true
 futures-util.workspace = true
+itertools.workspace = true
 lazy_static.workspace = true
+pin-project.workspace = true
 prometheus.workspace = true
 protobuf = { version = "2", features = ["bytes"] }
 raft-engine.workspace = true

src/log-store/src/kafka.rs

@@ -13,6 +13,9 @@
 // limitations under the License.
 
 pub(crate) mod client_manager;
+pub(crate) mod consumer;
+#[allow(unused)]
+pub(crate) mod index;
 pub mod log_store;
 pub(crate) mod producer;
 pub(crate) mod util;