Add streaming support and refactor Chat UI

- Add run_stream method to AgentCore for streaming output
- Add base_url parameter to LLM clients for OpenRouter support
- Add xbot module for new agent implementation
- Refactor Chat.vue into composable + components (ChatHeader, ChatMessage, ChatInput, ChatSidebar, ChatAgentSelector)
- Add ChatStream handler for SSE streaming in Go server
- Add UseXBot field to chat request

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/internal/service/agent_service.go

@@ -10,6 +10,8 @@ import (
 	"time"
 
 	"x-agents/server/internal/repository"
+
+	"github.com/gin-gonic/gin"
 )
 
 // AgentChatRequest Python Agent 对话请求
@@ -23,6 +25,7 @@ type AgentChatRequest struct {
 	ModelProvider  string `json:"model_provider,omitempty"`
 	APIKey         string `json:"api_key,omitempty"`
 	BaseURL        string `json:"base_url,omitempty"`
+	UseXBot        bool   `json:"use_xbot"`
 }
 
 // AgentChatResponse Python Agent 对话响应
@@ -186,3 +189,93 @@ func (s *AgentService) TeamChat(req TeamChatRequest) (*TeamChatResponse, error)
 
 	return &result, nil
 }
+
+// ChatStream 流式对话
+func (s *AgentService) ChatStream(c interface{}, agentID int, message, sessionID, modelID string, userID int) error {
+	// 获取 gin.Context
+	ginCtx, ok := c.(*gin.Context)
+	if !ok {
+		return fmt.Errorf("invalid context type")
+	}
+
+	// 初始化请求体
+	reqBody := map[string]interface{}{
+		"agent_id":   agentID,
+		"message":    message,
+		"user_id":    userID,
+		"session_id": sessionID,
+		"use_xbot":   false,
+	}
+
+	// 如果传入了 model_id，查询模型配置获取 api_key 和 base_url
+	if modelID != "" && s.modelRepo != nil {
+		model, err := s.modelRepo.FindByID(modelID)
+		if err != nil {
+			log.Printf("[ChatStream] Model not found: %s, error: %v", modelID, err)
+		} else if model != nil {
+			log.Printf("[ChatStream] Using model: provider=%s, model=%s, base_url=%s", model.Provider, model.Model, model.BaseURL)
+			// 将模型配置添加到请求体
+			reqBody["model_provider"] = model.Provider
+			reqBody["model_name"] = model.Model
+			reqBody["api_key"] = model.APIKey
+			reqBody["base_url"] = model.BaseURL
+		}
+	} else {
+		log.Printf("[ChatStream] modelID is empty or modelRepo is nil: modelID=%s, modelRepo=%v", modelID, s.modelRepo != nil)
+	}
+
+	streamURL := fmt.Sprintf("%s/agent/chat/stream", s.pythonURL)
+
+	jsonData, err := json.Marshal(reqBody)
+	if err != nil {
+		return fmt.Errorf("failed to marshal request: %w", err)
+	}
+
+	// 创建 HTTP 请求，设置不缓冲
+	httpReq, err := http.NewRequest("POST", streamURL, bytes.NewBuffer(jsonData))
+	if err != nil {
+		return fmt.Errorf("failed to create request: %w", err)
+	}
+	httpReq.Header.Set("Content-Type", "application/json")
+	httpReq.Header.Set("Accept", "text/event-stream")
+	httpReq.Header.Set("Cache-Control", "no-cache")
+
+	// 创建不缓冲的 HTTP 客户端
+	client := &http.Client{
+		Transport: &http.Transport{
+			DisableKeepAlives: true,
+		},
+	}
+	resp, err := client.Do(httpReq)
+	if err != nil {
+		return fmt.Errorf("failed to call python agent: %w", err)
+	}
+	defer resp.Body.Close()
+
+	// 设置 SSE 响应头
+	ginCtx.Header("Content-Type", "text/event-stream")
+	ginCtx.Header("Cache-Control", "no-cache")
+	ginCtx.Header("Connection", "keep-alive")
+	ginCtx.Header("X-Accel-Buffering", "no")
+
+	// 分块读取并转发，使用小 buffer 减少延迟
+	buf := make([]byte, 1024)
+	for {
+		n, err := resp.Body.Read(buf)
+		if n > 0 {
+			_, writeErr := ginCtx.Writer.Write(buf[:n])
+			if writeErr != nil {
+				break
+			}
+			// 强制刷新到客户端
+			if flusher, ok := ginCtx.Writer.(interface{ Flush() }); ok {
+				flusher.Flush()
+			}
+		}
+		if err != nil {
+			break
+		}
+	}
+
+	return nil
+}