feat: 添加群组和群成员信息获取功能

- 新增 action/group_member.go 文件，实现获取群组列表和群成员列表的方法
- 在 constants/uri.go 中定义群组相关的 API 路径常量
- 在 model/group.go 中添加群组和群成员的数据结构定义

action/group_member.go

@@ -0,0 +1,58 @@
+package action
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+
+	"git.lxtend.com/qqbot/config"
+	"git.lxtend.com/qqbot/constants"
+	"git.lxtend.com/qqbot/model"
+)
+
+func GetGroupMemberList(groupID int64) ([]model.GroupMember, error) {
+	fullURL := fmt.Sprintf("http://%s%s?group_id=%d", config.ConfigManager.GetConfig().NapcatHttpSrv, constants.GET_GROUP_MEMBER_LIST, groupID)
+
+	response, err := http.Get(fullURL)
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+
+	body, err := io.ReadAll(response.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var groupMemberListResponse model.GroupMemberListResponse
+	err = json.Unmarshal(body, &groupMemberListResponse)
+	if err != nil {
+		return nil, err
+	}
+
+	return groupMemberListResponse.Data, nil
+}
+
+func GetGroupList() ([]model.Group, error) {
+	fullURL := fmt.Sprintf("http://%s%s", config.ConfigManager.GetConfig().NapcatHttpSrv, constants.GET_GROUP_LIST)
+
+	response, err := http.Get(fullURL)
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+
+	body, err := io.ReadAll(response.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var groupListResponse model.GroupListResponse
+	err = json.Unmarshal(body, &groupListResponse)
+	if err != nil {
+		return nil, err
+	}
+
+	return groupListResponse.Data, nil
+}