fix(weixin): 扫码登录二维码真实可扫——前端生成QR(修坏图) + DecodeConfig容忍空config

weixin qrcode_img_content 是微信liteapp HTML页(非图片),后端fetch转base64只得<!doctype>→前端img坏图。
- 后端 login-qr 改返回 qrUrl(qrcode_img_content URL)+qrCode(原始qrcode),去掉坏 qrImage
- 前端用 qrcode 库从 qrUrl 生成真实二维码图片(微信扫https链接即开连接页), 新增 qrcode+@types/qrcode(纯UI依赖)
- DecodeConfig: nil config map 当空map解码(不报错), 否则 pending账号(空config)构建被跳过→未注册→登录端点404
- 测试更新(DecodeConfigNil/admin QR端点断言 qrUrl+qrCode)
- 另有 weixinAccountFor 裸weixin兜底(此前提交 d3b0921) 保证 accountId 命中
- 实测: login-qr 200{waiting, qrUrl=89}, 前端能看到可扫二维码
build/vet/test 全绿, 已部署.

internal/services/gateway/admin_channels_weixin.go

@@ -38,9 +38,12 @@ type weixinLoginAdmin interface {
 }
 
 // weixinLoginQRResponse is the wire shape of GET /admin/channels/{platform}/login-qr.
+// qrUrl is the WeChat QR image URL (qrcode_img_content) and qrCode is the raw scan
+// identifier (qrcode); the frontend renders a scannable QR from qrUrl, since the
+// liteapp URL is an HTML page that cannot be fetched as an image.
 type weixinLoginQRResponse struct {
 	QrUrl   string `json:"qrUrl,omitempty"`
-	QrImage string `json:"qrImage,omitempty"`
+	QrCode  string `json:"qrCode,omitempty"`
 	Status  string `json:"status"`
 }
 
@@ -77,9 +80,9 @@ func (s *Server) adminWeixinLoginQR(w http.ResponseWriter, r *http.Request) {
 	status, _ := wx.LoginStatus(r.Context())
 	s.auditClaims(r, "channel.weixin.login.qr", "ok")
 	writeJSON(w, http.StatusOK, weixinLoginQRResponse{
-		QrUrl:   qr.Image,
-		QrImage: qrImageDataURL(r.Context(), qr.Image),
-		Status:  status,
+		QrUrl:  qr.Image,
+		QrCode: qr.Qrcode,
+		Status: status,
 	})
 }
 

internal/services/gateway/admin_channels_weixin_test.go

@@ -196,19 +196,19 @@ func TestAdminWeixinLoginQR_ReturnsQRAndStatus(t *testing.T) {
 	}
 	var out struct {
 		Data struct {
-			QrUrl   string `json:"qrUrl"`
-			QrImage string `json:"qrImage"`
-			Status  string `json:"status"`
+			QrUrl  string `json:"qrUrl"`
+			QrCode string `json:"qrCode"`
+			Status string `json:"status"`
 		} `json:"data"`
 	}
 	if err := json.Unmarshal(body, &out); err != nil {
 		t.Fatalf("decode login-qr: %v", err)
 	}
 	if out.Data.QrUrl == "" {
-		t.Errorf("qrUrl empty, want the QR image content")
+		t.Errorf("qrUrl empty, want the QR image URL (qrcode_img_content)")
 	}
-	if !strings.HasPrefix(out.Data.QrImage, "data:image/png;base64,") {
-		t.Errorf("qrImage = %q, want a base64 data URL", out.Data.QrImage)
+	if out.Data.QrCode == "" {
+		t.Errorf("qrCode empty, want the raw scan identifier")
 	}
 	if out.Data.Status != weixin_ilink.LoginStatusWaiting && out.Data.Status != weixin_ilink.LoginStatusConfirmed {
 		t.Errorf("status = %q, want waiting|confirmed", out.Data.Status)