Support metric bundles and enable WS compression

Add support for bundling metrics and enable WebSocket compression. Introduces protocol.BundlePayload and MessageTypeBundle, and handles bundled messages on the server side (handleBundleMessage) by iterating items and forwarding each to metricService.HandleMetricData. On the agent side, add bundleWriter to collect outgoing MetricsPayloads, switch collectors to write into the bundle writer, and send a single bundle message when items exist. Also enable compression on the WebSocket upgrader and create a custom websocket.Dialer (with Proxy, HandshakeTimeout and EnableCompression). Minor logging/messages and import adjustments included.

pkg/agent/service/agent.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"log/slog"
+	"net/http"
 	"os"
 	"runtime"
 	"strings"
@@ -152,7 +153,11 @@ func (a *Agent) runOnce(ctx context.Context, onRegistered func()) error {
 	slog.Info("正在连接到服务器", "url", wsURL)
 
 	// 创建自定义的 Dialer
-	var dialer = websocket.DefaultDialer
+	dialer := &websocket.Dialer{
+		Proxy:            http.ProxyFromEnvironment,
+		HandshakeTimeout: 45 * time.Second,
+		EnableCompression: true,
+	}
 	if a.cfg.Server.InsecureSkipVerify {
 		dialer.TLSClientConfig = &tls.Config{
 			InsecureSkipVerify: true,
@@ -498,6 +503,26 @@ func (a *Agent) metricsLoop(ctx context.Context) {
 	}
 }
 
+type bundleWriter struct {
+	items []protocol.MetricsPayload
+}
+
+func (w *bundleWriter) WriteJSON(v interface{}) error {
+	msg, ok := v.(protocol.OutboundMessage)
+	if !ok {
+		return fmt.Errorf("invalid message type for bundleWriter")
+	}
+
+	if msg.Type == protocol.MessageTypeMetrics {
+		payload, ok := msg.Data.(protocol.MetricsPayload)
+		if ok {
+			w.items = append(w.items, payload)
+			return nil
+		}
+	}
+	return fmt.Errorf("only metrics messages can be bundled")
+}
+
 // collectAndSendAllMetrics 采集并发送所有动态指标
 func (a *Agent) collectAndSendAllMetrics(manager *collector.Manager) error {
 	if manager == nil {
@@ -514,58 +539,73 @@ func (a *Agent) collectAndSendAllMetrics(manager *collector.Manager) error {
 	}
 
 	writer := newOutboundWriter(conn, a.outboundBuffer)
+	bw := &bundleWriter{}
 	var hasError bool
 
 	// CPU 动态指标
-	if err := manager.CollectAndSendCPU(writer); err != nil {
-		slog.Warn("发送CPU指标失败", "error", err)
+	if err := manager.CollectAndSendCPU(bw); err != nil {
+		slog.Warn("采集CPU指标失败", "error", err)
 		hasError = true
 	}
 
 	// 内存动态指标
-	if err := manager.CollectAndSendMemory(writer); err != nil {
-		slog.Warn("发送内存指标失败", "error", err)
+	if err := manager.CollectAndSendMemory(bw); err != nil {
+		slog.Warn("采集内存指标失败", "error", err)
 		hasError = true
 	}
 
 	// 磁盘指标
-	if err := manager.CollectAndSendDisk(writer); err != nil {
-		slog.Warn("发送磁盘指标失败", "error", err)
+	if err := manager.CollectAndSendDisk(bw); err != nil {
+		slog.Warn("采集磁盘指标失败", "error", err)
 		hasError = true
 	}
 
 	// 磁盘 IO 指标
-	if err := manager.CollectAndSendDiskIO(writer); err != nil {
-		slog.Warn("发送磁盘IO指标失败", "error", err)
+	if err := manager.CollectAndSendDiskIO(bw); err != nil {
+		slog.Warn("采集磁盘IO指标失败", "error", err)
 		hasError = true
 	}
 
 	// 网络指标
-	if err := manager.CollectAndSendNetwork(writer); err != nil {
-		slog.Warn("发送网络指标失败", "error", err)
+	if err := manager.CollectAndSendNetwork(bw); err != nil {
+		slog.Warn("采集网络指标失败", "error", err)
 		hasError = true
 	}
 
 	// 网络连接统计
-	if err := manager.CollectAndSendNetworkConnection(writer); err != nil {
-		slog.Warn("发送网络连接统计失败", "error", err)
+	if err := manager.CollectAndSendNetworkConnection(bw); err != nil {
+		slog.Warn("采集网络连接统计失败", "error", err)
 		hasError = true
 	}
 
 	// 主机信息（包含 Load）
-	if err := manager.CollectAndSendHost(writer); err != nil {
-		slog.Warn("发送主机信息失败", "error", err)
+	if err := manager.CollectAndSendHost(bw); err != nil {
+		slog.Warn("采集主机信息失败", "error", err)
 		hasError = true
 	}
 
 	// GPU 信息（可选）
-	if err := manager.CollectAndSendGPU(writer); err != nil {
-		slog.Info("发送GPU信息失败", "error", err)
+	if err := manager.CollectAndSendGPU(bw); err != nil {
+		slog.Info("采集GPU信息失败", "error", err)
 	}
 
 	// 温度信息（可选）
-	if err := manager.CollectAndSendTemperature(writer); err != nil {
-		slog.Info("发送温度信息失败", "error", err)
+	if err := manager.CollectAndSendTemperature(bw); err != nil {
+		slog.Info("采集温度信息失败", "error", err)
+	}
+
+	// 发送打包后的指标
+	if len(bw.items) > 0 {
+		bundle := protocol.BundlePayload{
+			Items: bw.items,
+		}
+		if err := writer.WriteJSON(protocol.OutboundMessage{
+			Type: protocol.MessageTypeBundle,
+			Data: bundle,
+		}); err != nil {
+			slog.Warn("发送打包指标失败", "error", err)
+			hasError = true
+		}
 	}
 
 	if writer.buffered {