feat(cluster): implement Raft consensus with tracing and HTTP support

- Add Raft log and snapshot mechanisms for distributed consensus
- Integrate hyper HTTP server and client libraries for network communication
- Enhance tracing capabilities with structured logging and spans
- Add dependency tracking for new consensus-related crates
- Implement snapshot storage with serialization and persistence
- Add remote repository synchronization via Raft commands
- Include comprehensive tracing instrumentation across services

actor/sync.rs

@@ -355,3 +355,53 @@ fn update_local_ref(repo_path: &Path, ref_name: &str, new_oid: &str) {
         Err(e) => tracing::error!(ref_name = %ref_name, error = %e, "update-ref spawn failed"),
     }
 }
+
+/// Apply a committed Raft command to the local git repository.
+/// This is called on followers when they receive committed entries from the leader.
+pub fn apply_raft_command_to_repo(
+    repo_prefix: &Path,
+    command: &crate::actor::raft_log::Command,
+) {
+    match command {
+        crate::actor::raft_log::Command::RefUpdate {
+            relative_path,
+            ref_name,
+            old_oid: _,
+            new_oid,
+        } => {
+            let repo_path = repo_prefix.join(relative_path);
+            tracing::info!(
+                relative_path = %relative_path,
+                ref_name = %ref_name,
+                new_oid = %new_oid,
+                "applying RefUpdate from Raft log to local repo"
+            );
+            update_local_ref(&repo_path, ref_name, new_oid);
+        }
+        crate::actor::raft_log::Command::RegisterRepo {
+            relative_path,
+            storage_name: _,
+        } => {
+            tracing::info!(
+                relative_path = %relative_path,
+                "RegisterRepo from Raft log (no git action needed)"
+            );
+        }
+        crate::actor::raft_log::Command::RemoveRepo { relative_path } => {
+            tracing::info!(
+                relative_path = %relative_path,
+                "RemoveRepo from Raft log (no git action needed)"
+            );
+        }
+        crate::actor::raft_log::Command::SetPrimary {
+            storage_name,
+            relative_paths,
+        } => {
+            tracing::info!(
+                storage_name = %storage_name,
+                paths = relative_paths.len(),
+                "SetPrimary from Raft log (no git action needed)"
+            );
+        }
+    }
+}