fix(groups): keep group traffic totals stable across client resets and deletes

ListGroups displays live_sum(client_traffics) minus the group's stored
reset baseline, but only ResetGroupTraffic ever moved the baseline. Any
client-level operation that zeroed or deleted traffic rows (single/bulk
reset, client delete, removing a client's last inbound) shrank the live
sum and silently subtracted that client's history from the group total.

Shift the baseline down by the removed counters inside the same
transaction, so group totals only change through group reset. Derived
groups without a stored row get one with a negative baseline, which the
existing clamp handles.

Closes #5675

internal/web/service/client_groups.go

@@ -8,6 +8,8 @@ import (
 	"github.com/mhsanaei/3x-ui/v3/internal/database"
 	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
 	"github.com/mhsanaei/3x-ui/v3/internal/util/common"
+
+	"gorm.io/gorm"
 )
 
 type GroupSummary struct {
@@ -69,6 +71,57 @@ func (s *ClientService) ListGroups() ([]GroupSummary, error) {
 	return out, nil
 }
 
+// adjustGroupBaselinesForRemovedTraffic shifts group baselines down by the clients'
+// current counters so ListGroups totals survive a traffic reset or client delete (#5675).
+func adjustGroupBaselinesForRemovedTraffic(tx *gorm.DB, emails []string) error {
+	if len(emails) == 0 {
+		return nil
+	}
+	type groupDelta struct {
+		Name string
+		Up   int64
+		Down int64
+	}
+	totals := make(map[string]*groupDelta)
+	for _, batch := range chunkStrings(emails, sqlInChunk) {
+		var part []groupDelta
+		if err := tx.Table("clients AS c").
+			Select("c.group_name AS name, COALESCE(SUM(ct.up), 0) AS up, COALESCE(SUM(ct.down), 0) AS down").
+			Joins("JOIN client_traffics ct ON ct.email = c.email").
+			Where("c.group_name <> '' AND c.email IN ?", batch).
+			Group("c.group_name").
+			Scan(&part).Error; err != nil {
+			return err
+		}
+		for i := range part {
+			if agg, ok := totals[part[i].Name]; ok {
+				agg.Up += part[i].Up
+				agg.Down += part[i].Down
+			} else {
+				totals[part[i].Name] = &part[i]
+			}
+		}
+	}
+	for name, d := range totals {
+		if d.Up == 0 && d.Down == 0 {
+			continue
+		}
+		res := tx.Model(&model.ClientGroup{}).Where("name = ?", name).Updates(map[string]any{
+			"reset_up":   gorm.Expr("reset_up - ?", d.Up),
+			"reset_down": gorm.Expr("reset_down - ?", d.Down),
+		})
+		if res.Error != nil {
+			return res.Error
+		}
+		if res.RowsAffected == 0 {
+			if err := tx.Create(&model.ClientGroup{Name: name, ResetUp: -d.Up, ResetDown: -d.Down}).Error; err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
 func (s *ClientService) EmailsByGroup(name string) ([]string, error) {
 	name = strings.TrimSpace(name)
 	if name == "" {