refactor: 流量系统重构 — 增量累加算法 + 日粒度缓冲 + 旧详单清理

核心改造：
- 增量算法：流量计算从覆盖式改为增量累加（gateway - lastReading），支持上游运营商重置检测
- 日流量缓冲：insertDataUsageRecord 改为 Redis INCRBYFLOAT，每日凌晨落盘到 tb_card_daily_usage
- 运营商：新增 data_reset_day 字段（联通=27，其余=1）
- IoT卡：新增 last_gateway_reading_mb 字段存储上次网关读数
- 查询层：新建 TrafficQueryService 合并 Redis（今日）+ DB（历史）数据源
- 清理：删除 DataUsageRecord model/store，移除 polling_handler 旧引用

迁移：000094-000097（carrier字段、iot_card字段、数据初始化、日流量表）

internal/store/postgres/card_daily_usage_store.go

@@ -0,0 +1,57 @@
+package postgres
+
+import (
+	"context"
+	"time"
+
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+
+	"github.com/break/junhong_cmp_fiber/internal/model"
+)
+
+// CardDailyUsageStore 卡日流量记录存储
+// 同时供落盘任务和查询层使用
+type CardDailyUsageStore struct {
+	db *gorm.DB
+}
+
+func NewCardDailyUsageStore(db *gorm.DB) *CardDailyUsageStore {
+	return &CardDailyUsageStore{db: db}
+}
+
+// Upsert 覆盖写入日流量记录（幂等安全）
+// ON CONFLICT (iot_card_id, date) DO UPDATE SET usage_mb = EXCLUDED.usage_mb
+func (s *CardDailyUsageStore) Upsert(ctx context.Context, record *model.CardDailyUsage) error {
+	return s.db.WithContext(ctx).
+		Clauses(clause.OnConflict{
+			Columns:   []clause.Column{{Name: "iot_card_id"}, {Name: "date"}},
+			DoUpdates: clause.AssignmentColumns([]string{"usage_mb", "updated_at"}),
+		}).
+		Create(record).Error
+}
+
+// UpsertBatch 批量覆盖写入日流量记录
+func (s *CardDailyUsageStore) UpsertBatch(ctx context.Context, records []*model.CardDailyUsage) error {
+	if len(records) == 0 {
+		return nil
+	}
+	return s.db.WithContext(ctx).
+		Clauses(clause.OnConflict{
+			Columns:   []clause.Column{{Name: "iot_card_id"}, {Name: "date"}},
+			DoUpdates: clause.AssignmentColumns([]string{"usage_mb", "updated_at"}),
+		}).
+		CreateInBatches(records, 200).Error
+}
+
+// ListByCardIDAndDateRange 查询卡在日期范围内的日流量记录
+func (s *CardDailyUsageStore) ListByCardIDAndDateRange(ctx context.Context, cardID uint, startDate, endDate time.Time) ([]*model.CardDailyUsage, error) {
+	var records []*model.CardDailyUsage
+	if err := s.db.WithContext(ctx).
+		Where("iot_card_id = ? AND date >= ? AND date <= ?", cardID, startDate, endDate).
+		Order("date ASC").
+		Find(&records).Error; err != nil {
+		return nil, err
+	}
+	return records, nil
+}

internal/store/postgres/data_usage_record_store.go

@@ -1,91 +0,0 @@
-package postgres
-
-import (
-	"context"
-	"time"
-
-	"gorm.io/gorm"
-
-	"github.com/break/junhong_cmp_fiber/internal/model"
-)
-
-// DataUsageRecordStore 流量使用记录存储
-type DataUsageRecordStore struct {
-	db *gorm.DB
-}
-
-// NewDataUsageRecordStore 创建流量使用记录存储实例
-func NewDataUsageRecordStore(db *gorm.DB) *DataUsageRecordStore {
-	return &DataUsageRecordStore{db: db}
-}
-
-// Create 创建流量使用记录
-func (s *DataUsageRecordStore) Create(ctx context.Context, record *model.DataUsageRecord) error {
-	return s.db.WithContext(ctx).Create(record).Error
-}
-
-// CreateBatch 批量创建流量使用记录
-func (s *DataUsageRecordStore) CreateBatch(ctx context.Context, records []*model.DataUsageRecord) error {
-	if len(records) == 0 {
-		return nil
-	}
-	return s.db.WithContext(ctx).CreateInBatches(records, 100).Error
-}
-
-// GetLatestByCardID 获取卡的最新流量记录
-func (s *DataUsageRecordStore) GetLatestByCardID(ctx context.Context, cardID uint) (*model.DataUsageRecord, error) {
-	var record model.DataUsageRecord
-	if err := s.db.WithContext(ctx).
-		Where("iot_card_id = ?", cardID).
-		Order("check_time DESC").
-		First(&record).Error; err != nil {
-		return nil, err
-	}
-	return &record, nil
-}
-
-// ListByCardID 获取卡的流量记录列表
-func (s *DataUsageRecordStore) ListByCardID(ctx context.Context, cardID uint, startTime, endTime *time.Time, page, pageSize int) ([]*model.DataUsageRecord, int64, error) {
-	var records []*model.DataUsageRecord
-	var total int64
-
-	query := s.db.WithContext(ctx).Model(&model.DataUsageRecord{}).Where("iot_card_id = ?", cardID)
-
-	if startTime != nil {
-		query = query.Where("check_time >= ?", *startTime)
-	}
-	if endTime != nil {
-		query = query.Where("check_time <= ?", *endTime)
-	}
-
-	if err := query.Count(&total).Error; err != nil {
-		return nil, 0, err
-	}
-
-	offset := (page - 1) * pageSize
-	if err := query.Order("check_time DESC").Offset(offset).Limit(pageSize).Find(&records).Error; err != nil {
-		return nil, 0, err
-	}
-
-	return records, total, nil
-}
-
-// DeleteOlderThan 删除指定时间之前的记录（用于数据清理）
-func (s *DataUsageRecordStore) DeleteOlderThan(ctx context.Context, before time.Time, batchSize int) (int64, error) {
-	result := s.db.WithContext(ctx).
-		Where("check_time < ?", before).
-		Limit(batchSize).
-		Delete(&model.DataUsageRecord{})
-	return result.RowsAffected, result.Error
-}
-
-// CountByCardID 统计卡的流量记录数量
-func (s *DataUsageRecordStore) CountByCardID(ctx context.Context, cardID uint) (int64, error) {
-	var count int64
-	if err := s.db.WithContext(ctx).Model(&model.DataUsageRecord{}).
-		Where("iot_card_id = ?", cardID).
-		Count(&count).Error; err != nil {
-		return 0, err
-	}
-	return count, nil
-}