AX Agent 채팅 엔진 최종 응답 커밋형으로 정상화

claw-code 기준으로 AX Agent 채팅 전송 흐름을 준비, 실행, 최종 assistant 커밋, 재렌더 순서로 다시 정리했습니다.

ChatWindow의 SendMessageAsync와 SendRegenerateAsync에서 임시 assistant 메시지와 임시 스트리밍 컨테이너를 먼저 만드는 경로를 제거하고, 실행이 끝난 뒤 최종 assistant 텍스트만 conversation/session에 커밋하도록 수정했습니다.

OnAgentEvent는 실행 로그 배너를 즉시 UI에 직접 꽂지 않고 conversation ExecutionEvents에 먼저 저장한 뒤 ShowExecutionHistory가 켜진 경우에만 RenderMessages 기반으로 다시 그리게 바꿔 Cowork/Code의 플래시 잔상과 중복 표시를 줄였습니다.

AxAgentExecutionEngine도 Chat 실행을 스트리밍 UI 의존이 없는 최종 응답 커밋형 모드로 정리했습니다. 검증은 dotnet build src/AxCopilot/AxCopilot.csproj -c Release -v minimal -p:OutputPath=bin\\verify\\ -p:IntermediateOutputPath=obj\\verify\\ 기준 경고 0개, 오류 0개입니다.

src/AxCopilot/Services/Agent/AxAgentExecutionEngine.cs

@@ -0,0 +1,128 @@
+using AxCopilot.Models;
+using AxCopilot.Services;
+
+namespace AxCopilot.Services.Agent;
+
+/// <summary>
+/// AX Agent execution-prep engine.
+/// Inspired by the `claw-code` split between input preparation and session execution,
+/// so the UI layer stops owning message assembly and final assistant commit logic.
+/// </summary>
+public sealed class AxAgentExecutionEngine
+{
+    public sealed record PreparedTurn(List<ChatMessage> Messages);
+    public sealed record ExecutionMode(bool UseAgentLoop, bool UseStreamingTransport, string? TaskSystemPrompt);
+
+    public IReadOnlyList<string> BuildPromptStack(
+        string? conversationSystem,
+        string? slashSystem,
+        string? taskSystem = null)
+    {
+        var prompts = new List<string>();
+        if (!string.IsNullOrWhiteSpace(conversationSystem))
+            prompts.Add(conversationSystem.Trim());
+        if (!string.IsNullOrWhiteSpace(slashSystem))
+            prompts.Add(slashSystem.Trim());
+        if (!string.IsNullOrWhiteSpace(taskSystem))
+            prompts.Add(taskSystem.Trim());
+        return prompts;
+    }
+
+    public ExecutionMode ResolveExecutionMode(
+        string runTab,
+        bool streamingEnabled,
+        string resolvedService,
+        string? coworkSystemPrompt,
+        string? codeSystemPrompt)
+    {
+        if (string.Equals(runTab, "Cowork", StringComparison.OrdinalIgnoreCase))
+            return new ExecutionMode(true, false, coworkSystemPrompt);
+
+        if (string.Equals(runTab, "Code", StringComparison.OrdinalIgnoreCase))
+            return new ExecutionMode(true, false, codeSystemPrompt);
+
+        return new ExecutionMode(false, false, null);
+    }
+
+    public PreparedTurn PrepareTurn(
+        ChatConversation conversation,
+        IEnumerable<string?> systemPrompts,
+        string? fileContext = null,
+        IReadOnlyList<ImageAttachment>? images = null)
+    {
+        var outbound = conversation.Messages
+            .Select(CloneMessage)
+            .ToList();
+
+        if (!string.IsNullOrWhiteSpace(fileContext))
+        {
+            var lastUserIndex = outbound.FindLastIndex(m => string.Equals(m.Role, "user", StringComparison.OrdinalIgnoreCase));
+            if (lastUserIndex >= 0)
+                outbound[lastUserIndex].Content = (outbound[lastUserIndex].Content ?? string.Empty) + fileContext;
+        }
+
+        if (images is { Count: > 0 })
+        {
+            var lastUserIndex = outbound.FindLastIndex(m => string.Equals(m.Role, "user", StringComparison.OrdinalIgnoreCase));
+            if (lastUserIndex >= 0)
+                outbound[lastUserIndex].Images = images.Select(CloneImage).ToList();
+        }
+
+        var promptList = systemPrompts
+            .Where(prompt => !string.IsNullOrWhiteSpace(prompt))
+            .Select(prompt => prompt!.Trim())
+            .ToList();
+
+        for (var i = promptList.Count - 1; i >= 0; i--)
+            outbound.Insert(0, new ChatMessage { Role = "system", Content = promptList[i] });
+
+        return new PreparedTurn(outbound);
+    }
+
+    public ChatMessage CommitAssistantMessage(
+        ChatSessionStateService? session,
+        ChatConversation conversation,
+        string tab,
+        string content,
+        ChatStorageService? storage = null)
+    {
+        var assistant = new ChatMessage
+        {
+            Role = "assistant",
+            Content = content,
+        };
+
+        if (session != null)
+        {
+            session.AppendMessage(tab, assistant, storage);
+            return assistant;
+        }
+
+        conversation.Messages.Add(assistant);
+        conversation.UpdatedAt = DateTime.Now;
+        return assistant;
+    }
+
+    private static ChatMessage CloneMessage(ChatMessage source)
+    {
+        return new ChatMessage
+        {
+            Role = source.Role,
+            Content = source.Content,
+            Timestamp = source.Timestamp,
+            MetaRunId = source.MetaRunId,
+            AttachedFiles = source.AttachedFiles?.ToList(),
+            Images = source.Images?.Select(CloneImage).ToList(),
+        };
+    }
+
+    private static ImageAttachment CloneImage(ImageAttachment source)
+    {
+        return new ImageAttachment
+        {
+            Base64 = source.Base64,
+            MimeType = source.MimeType,
+            FileName = source.FileName,
+        };
+    }
+}