fix: 适配X-Claude-Code-Session-Id头

backend/internal/service/gateway_service.go

@@ -369,6 +369,8 @@ var allowedHeaders = map[string]bool{
 	"user-agent":                                true,
 	"content-type":                              true,
 	"accept-encoding":                           true,
+	"x-claude-code-session-id":                  true,
+	"x-client-request-id":                       true,
 }
 
 // GatewayCache 定义网关服务的缓存操作接口。
@@ -5756,6 +5758,15 @@ func (s *GatewayService) buildUpstreamRequest(ctx context.Context, c *gin.Contex
 		}
 	}
 
+	// 同步 X-Claude-Code-Session-Id 头：取 body 中已处理的 metadata.user_id 的 session_id 覆盖
+	if sessionHeader := getHeaderRaw(req.Header, "X-Claude-Code-Session-Id"); sessionHeader != "" {
+		if uid := gjson.GetBytes(body, "metadata.user_id").String(); uid != "" {
+			if parsed := ParseMetadataUserID(uid); parsed != nil {
+				setHeaderRaw(req.Header, "X-Claude-Code-Session-Id", parsed.SessionID)
+			}
+		}
+	}
+
 	// === DEBUG: 打印上游转发请求（headers + body 摘要），与 CLIENT_ORIGINAL 对比 ===
 	s.debugLogGatewaySnapshot("UPSTREAM_FORWARD", req.Header, body, map[string]string{
 		"url":                 req.URL.String(),
@@ -8475,6 +8486,15 @@ func (s *GatewayService) buildCountTokensRequest(ctx context.Context, c *gin.Con
 		}
 	}
 
+	// 同步 X-Claude-Code-Session-Id 头：取 body 中已处理的 metadata.user_id 的 session_id 覆盖
+	if sessionHeader := getHeaderRaw(req.Header, "X-Claude-Code-Session-Id"); sessionHeader != "" {
+		if uid := gjson.GetBytes(body, "metadata.user_id").String(); uid != "" {
+			if parsed := ParseMetadataUserID(uid); parsed != nil {
+				setHeaderRaw(req.Header, "X-Claude-Code-Session-Id", parsed.SessionID)
+			}
+		}
+	}
+
 	if c != nil && tokenType == "oauth" {
 		c.Set(claudeMimicDebugInfoKey, buildClaudeMimicDebugLine(req, body, account, tokenType, mimicClaudeCode))
 	}

backend/internal/service/header_util.go

@@ -36,6 +36,11 @@ var headerWireCasing = map[string]string{
 	"sec-fetch-mode":                            "sec-fetch-mode",
 	"accept-encoding":                           "accept-encoding",
 	"authorization":                             "authorization",
+
+	// Claude Code 2.1.87+ 新增 header
+	"x-claude-code-session-id": "X-Claude-Code-Session-Id",
+	"x-client-request-id":      "x-client-request-id",
+	"content-length":           "content-length",
 }
 
 // headerWireOrder 定义真实 Claude CLI 发送 header 的顺序（基于抓包）。
@@ -55,11 +60,14 @@ var headerWireOrder = []string{
 	"authorization",
 	"x-app",
 	"User-Agent",
+	"X-Claude-Code-Session-Id",
 	"content-type",
 	"anthropic-beta",
+	"x-client-request-id",
 	"accept-language",
 	"sec-fetch-mode",
 	"accept-encoding",
+	"content-length",
 	"x-stainless-helper-method",
 }