feat: 用户徽章与等级体系，积分经济管理重构

- 新增徽章系统：badge 服务与 handler、管理端配置页、BadgeChip/LevelBadge 展示组件
- 新增等级模型：model/level 及前端 levels 元数据
- 管理端经济模块拆分为 points/badges/levels 独立页面，EconomySettings 迁入设置
- 积分、签到、评论等服务适配等级与徽章逻辑

backend/service/checkin.go

@@ -2,13 +2,15 @@ package service
 
 import (
 	"errors"
+	"log"
+	"strconv"
 	"time"
 
 	"github.com/freefire/jiang13-bbs/model"
 	"gorm.io/gorm"
 )
 
-// DailyCheckinPoints 每日签到固定积分
+// DailyCheckinPoints 每日签到默认基础分（可被设置 points_checkin_base 覆盖）
 const DailyCheckinPoints = 5
 
 // maxStreakScan 连续天数最多向前回溯的天数
@@ -22,18 +24,38 @@ type CheckinStatus struct {
 	CheckedToday bool `json:"checked_today"`
 	Streak       int  `json:"streak"`       // 连续签到天数
 	TotalPoints  int  `json:"total_points"` // 累计积分（可用余额）
-	TodayPoints  int  `json:"today_points"` // 今日签到可得积分
+	TodayPoints  int  `json:"today_points"` // 今日签到可得基础积分（连续加成另行入账，流水可见）
 }
 
 // CheckinService 每日签到
 type CheckinService struct {
-	db *gorm.DB
+	db      *gorm.DB
+	setting *SettingService
 }
 
 func NewCheckinService(db *gorm.DB) *CheckinService {
 	return &CheckinService{db: db}
 }
 
+// WithSetting 注入站点设置（积分增长规则；未注入时用默认值）
+func (s *CheckinService) WithSetting(setting *SettingService) *CheckinService {
+	s.setting = setting
+	return s
+}
+
+// rules 读取积分规则；未注入或读取失败回落默认值（签到可用性优先于规则精度）
+func (s *CheckinService) rules() PointsRules {
+	if s.setting == nil {
+		return PointsRules{CheckinBase: DefaultPointsCheckinBase, StreakEveryDays: DefaultPointsStreakEveryDays}
+	}
+	rules, err := s.setting.PointsRules()
+	if err != nil {
+		log.Printf("[checkin] 读取积分规则失败，使用默认值: %v", err)
+		return PointsRules{CheckinBase: DefaultPointsCheckinBase, StreakEveryDays: DefaultPointsStreakEveryDays}
+	}
+	return rules
+}
+
 // localDay 取本地时区零点日期
 func localDay(t time.Time) time.Time {
 	y, m, d := t.Date()
@@ -53,9 +75,25 @@ func streakFrom(dates map[string]bool, anchor time.Time) int {
 	return streak
 }
 
+// streakDatesInTx 从事务连接查询 anchor 起回溯窗口内的签到日期集合
+func streakDatesInTx(tx *gorm.DB, userID uint, anchor time.Time) (map[string]bool, error) {
+	var dates []time.Time
+	if err := tx.Model(&model.Checkin{}).
+		Where("user_id = ? AND checkin_date >= ?", userID, anchor.AddDate(0, 0, -maxStreakScan)).
+		Pluck("checkin_date", &dates).Error; err != nil {
+		return nil, err
+	}
+	dateSet := make(map[string]bool, len(dates))
+	for _, d := range dates {
+		dateSet[localDay(d).Format("2006-01-02")] = true
+	}
+	return dateSet, nil
+}
+
 // Status 查询用户签到状态
 func (s *CheckinService) Status(userID uint) (*CheckinStatus, error) {
 	today := localDay(time.Now())
+	base := s.rules().CheckinBase
 
 	var todayRow model.Checkin
 	err := s.db.Where("user_id = ? AND checkin_date::date = ?::date", userID, today).
@@ -73,16 +111,10 @@ func (s *CheckinService) Status(userID uint) (*CheckinStatus, error) {
 	if !checkedToday {
 		anchor = today.AddDate(0, 0, -1)
 	}
-	var dates []time.Time
-	if err := s.db.Model(&model.Checkin{}).
-		Where("user_id = ? AND checkin_date >= ?", userID, anchor.AddDate(0, 0, -maxStreakScan)).
-		Pluck("checkin_date", &dates).Error; err != nil {
+	dateSet, err := streakDatesInTx(s.db, userID, anchor)
+	if err != nil {
 		return nil, err
 	}
-	dateSet := make(map[string]bool, len(dates))
-	for _, d := range dates {
-		dateSet[localDay(d).Format("2006-01-02")] = true
-	}
 
 	var total int64
 	if err := s.db.Model(&model.User{}).
@@ -95,13 +127,15 @@ func (s *CheckinService) Status(userID uint) (*CheckinStatus, error) {
 		CheckedToday: checkedToday,
 		Streak:       streakFrom(dateSet, anchor),
 		TotalPoints:  int(total),
-		TodayPoints:  DailyCheckinPoints,
+		TodayPoints:  base,
 	}, nil
 }
 
-// CheckIn 执行今日签到（每日一条，唯一索引兜底并发）
+// CheckIn 执行今日签到（每日一条，唯一索引兜底并发）。
+// 基础分与连续签到里程碑加成在同一事务内入账（加成规则可配置：每满 N 天额外 +X）。
 func (s *CheckinService) CheckIn(userID uint) (*CheckinStatus, error) {
 	today := localDay(time.Now())
+	rules := s.rules()
 
 	var status *CheckinStatus
 	err := s.db.Transaction(func(tx *gorm.DB) error {
@@ -117,15 +151,28 @@ func (s *CheckinService) CheckIn(userID uint) (*CheckinStatus, error) {
 		row := model.Checkin{
 			UserID:      userID,
 			CheckinDate: today,
-			Points:      DailyCheckinPoints,
+			Points:      rules.CheckinBase,
 		}
 		if err := tx.Create(&row).Error; err != nil {
 			return err
 		}
 		// 同步入账到用户积分余额
-		if _, err := CreditTx(tx, userID, DailyCheckinPoints, model.PointReasonCheckin, "checkin", row.ID, "每日签到"); err != nil {
+		if _, err := CreditTx(tx, userID, rules.CheckinBase, model.PointReasonCheckin, "checkin", row.ID, "每日签到"); err != nil {
 			return err
 		}
+		// 连续签到里程碑加成（每满 N 天额外 +X；N=0 或加成=0 时关闭）
+		if rules.StreakEveryDays > 0 && rules.StreakBonus > 0 {
+			dateSet, err := streakDatesInTx(tx, userID, today)
+			if err != nil {
+				return err
+			}
+			if streak := streakFrom(dateSet, today); streak > 0 && streak%rules.StreakEveryDays == 0 {
+				if _, err := CreditTx(tx, userID, rules.StreakBonus, model.PointReasonStreakBonus, "checkin", row.ID,
+					"连续签到 "+strconv.Itoa(streak)+" 天奖励"); err != nil {
+					return err
+				}
+			}
+		}
 		return nil
 	})
 	if err != nil {