feat(channel): KOOK 渠道适配器 + 框架兼容增强(wsutil/httpclient)

- plugins/channels/kook: config/adapter/gateway/websocket/send/message/errors — 实现 PlatformAdapter 13方法
  - WS 有状态网关: 取gateway地址→连WS→信令0/1/2/3/4/6 + 30s心跳/6s超时 + resume(拼接sn/session_id) + 指数退避重连
  - 收事件: 信令0 → UnifiedMessage(word注 channel_type/type/target_id/extra.author→字段)
  - 发消息: /message/create(频道) + /direct-message/create(私聊,修正正确端点,非user-chat) + Bearer鉴权
  - 注册 channels.go + CHANNELS_JSON 多账号 + channelbridge.configured 加 kook(bot_token非空才连)
- 框架增强: internal/channel/adapter/wsutil(连接管理/心跳/重连/resume骨架,复用gorilla,KOOK用上) + httpclient(Bearer+envelope归一,KOOK用)
- 全仓 go build/vet/test 绿, 零新依赖(复用餐gorilla), 未动telegram/qq/weixin/webhook契约
- §4.6 隔离/黑白名单/第三方边界未破坏

注: KOOK WS/WH 双模式待补(ReceiveMode), 实测需主人提供 CHANNEL_KOOK_TOKEN

internal/channel/adapter/httpclient/client_test.go

@@ -0,0 +1,96 @@
+package httpclient
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"io"
+	"log/slog"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"sync"
+	"testing"
+
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/logger"
+)
+
+func discardLogger() *slog.Logger { return logger.New(logger.Options{Out: io.Discard}) }
+
+func TestGetJSON_EnvelopeAndAuth(t *testing.T) {
+	t.Parallel()
+	var mu sync.Mutex
+	var auth string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		mu.Lock()
+		auth = r.Header.Get("Authorization")
+		mu.Unlock()
+		_ = json.NewEncoder(w).Encode(map[string]any{
+			"code": 0, "message": "ok",
+			"data": map[string]any{"url": "wss://gw.example.com/gateway"},
+		})
+	}))
+	defer srv.Close()
+
+	c := New(
+		WithBaseURL(srv.URL),
+		WithToken("secret-token"),
+		WithHTTPClient(srv.Client()),
+		WithLogger(discardLogger()),
+	)
+	data, err := c.GetJSON(context.Background(), "/gateway/index", url.Values{"compress": {"0"}})
+	if err != nil {
+		t.Fatalf("GetJSON: %v", err)
+	}
+	if string(data) != `{"url":"wss://gw.example.com/gateway"}` {
+		t.Errorf("data = %s", string(data))
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	if auth != "Bearer secret-token" {
+		t.Errorf("Authorization = %q, want Bearer secret-token", auth)
+	}
+}
+
+func TestDoJSON_NonZeroCode(t *testing.T) {
+	t.Parallel()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_ = json.NewEncoder(w).Encode(map[string]any{"code": 40101, "message": "invalid token", "data": struct{}{}})
+	}))
+	defer srv.Close()
+	c := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()), WithLogger(discardLogger()))
+	_, err := c.DoJSON(context.Background(), http.MethodPost, "/message/create", map[string]any{"a": 1})
+	if !errors.Is(err, ErrAPI) {
+		t.Fatalf("err = %v, want ErrAPI", err)
+	}
+}
+
+func TestDoJSON_StatusError(t *testing.T) {
+	t.Parallel()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusUnauthorized)
+		_, _ = w.Write([]byte("unauthorized"))
+	}))
+	defer srv.Close()
+	c := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()), WithLogger(discardLogger()))
+	_, err := c.DoJSON(context.Background(), http.MethodGet, "/gateway/index", nil)
+	if !errors.Is(err, ErrAPI) {
+		t.Fatalf("err = %v, want ErrAPI", err)
+	}
+}
+
+func TestGetJSON_NonEnvelopeBodyPassedThrough(t *testing.T) {
+	t.Parallel()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		_, _ = w.Write([]byte(`[1,2,3]`))
+	}))
+	defer srv.Close()
+	c := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()), WithLogger(discardLogger()))
+	data, err := c.GetJSON(context.Background(), "/list", nil)
+	if err != nil {
+		t.Fatalf("GetJSON: %v", err)
+	}
+	if string(data) != "[1,2,3]" {
+		t.Errorf("data = %s, want [1,2,3]", string(data))
+	}
+}