refactor(edge): Server 协议统一与 wsclient 收敛（Phase 3 Batch 3）

- openflare/agent/relay/flared 协议类型改为 pkg/protocol 别名，删除重复 struct
- 新增 edge/wsclient Preset 表，三组件 wsclient 改为薄包装
- 更新设计文档、计划与 changelog

internal/apps/flared/wsclient/client.go

@@ -2,74 +2,29 @@ package wsclient
 
 import (
 	"context"
-	"encoding/json"
 	"time"
 
-	service "github.com/Rain-kl/Wavelet/pkg/protocol"
-	shared "github.com/Rain-kl/Wavelet/pkg/wsclient"
+	edgews "github.com/Rain-kl/Wavelet/internal/apps/edge/wsclient"
 )
 
-type WSMessage = shared.WSMessage
-type MessageHandler = shared.MessageHandler
+type WSMessage = edgews.WSMessage
+type MessageHandler = edgews.MessageHandler
+type Connection = edgews.Connection
 
 type Client struct {
-	sharedClient *shared.Client
+	inner *edgews.Client
 }
 
-type Connection struct {
-	sharedConn *shared.Connection
-}
-
-func New(baseURL string, token string, timeout time.Duration) *Client {
+func New(baseURL, token string, timeout time.Duration) *Client {
 	return &Client{
-		sharedClient: shared.New(shared.Config{
-			BaseURL:   baseURL,
-			Token:     token,
-			Timeout:   timeout,
-			HeaderKey: "X-Tunnel-Token",
-			WSPath:    "/api/v1/tunnel/ws",
-		}),
+		inner: edgews.New(edgews.PresetFlared, baseURL, token, timeout),
 	}
 }
 
 func (c *Client) SetToken(token string) {
-	c.sharedClient.SetToken(token)
+	c.inner.SetToken(token)
 }
 
 func (c *Client) Connect(ctx context.Context) (*Connection, error) {
-	conn, err := c.sharedClient.Connect(ctx)
-	if err != nil {
-		return nil, err
-	}
-	return &Connection{sharedConn: conn}, nil
-}
-
-func (conn *Connection) SendPing() error {
-	return conn.sharedConn.SendMessage("ping", nil)
-}
-
-func (conn *Connection) SendPong() error {
-	return conn.sharedConn.SendMessage("pong", nil)
-}
-
-func (conn *Connection) Receive() (service.WSMessage, error) {
-	var raw struct {
-		Type    string          `json:"type"`
-		Payload json.RawMessage `json:"payload,omitempty"`
-	}
-	if err := conn.sharedConn.Receive(&raw); err != nil {
-		return service.WSMessage{}, err
-	}
-	return service.WSMessage{
-		Type:    raw.Type,
-		Payload: raw.Payload,
-	}, nil
-}
-
-func (conn *Connection) RunReceiveLoop(ctx context.Context, handler shared.MessageHandler) error {
-	return conn.sharedConn.RunReceiveLoop(ctx, handler)
-}
-
-func (conn *Connection) Close() error {
-	return conn.sharedConn.Close()
-}
+	return c.inner.Connect(ctx)
+}