feat: complete final jetstream parity transport and runtime baselines

src/NATS.Server/Raft/RaftTransport.cs

@@ -0,0 +1,44 @@
+namespace NATS.Server.Raft;
+
+public interface IRaftTransport
+{
+    Task<IReadOnlyList<AppendResult>> AppendEntriesAsync(string leaderId, IReadOnlyList<string> followerIds, RaftLogEntry entry, CancellationToken ct);
+    Task<VoteResponse> RequestVoteAsync(string candidateId, string voterId, VoteRequest request, CancellationToken ct);
+}
+
+public sealed class InMemoryRaftTransport : IRaftTransport
+{
+    private readonly Dictionary<string, RaftNode> _nodes = new(StringComparer.Ordinal);
+
+    public void Register(RaftNode node)
+    {
+        _nodes[node.Id] = node;
+    }
+
+    public Task<IReadOnlyList<AppendResult>> AppendEntriesAsync(string leaderId, IReadOnlyList<string> followerIds, RaftLogEntry entry, CancellationToken ct)
+    {
+        var results = new List<AppendResult>(followerIds.Count);
+        foreach (var followerId in followerIds)
+        {
+            if (_nodes.TryGetValue(followerId, out var node))
+            {
+                node.ReceiveReplicatedEntry(entry);
+                results.Add(new AppendResult { FollowerId = followerId, Success = true });
+            }
+            else
+            {
+                results.Add(new AppendResult { FollowerId = followerId, Success = false });
+            }
+        }
+
+        return Task.FromResult<IReadOnlyList<AppendResult>>(results);
+    }
+
+    public Task<VoteResponse> RequestVoteAsync(string candidateId, string voterId, VoteRequest request, CancellationToken ct)
+    {
+        if (_nodes.TryGetValue(voterId, out var node))
+            return Task.FromResult(node.GrantVote(request.Term));
+
+        return Task.FromResult(new VoteResponse { Granted = false });
+    }
+}