fix(clients): use client_inbounds link to resolve inbound, not stale id

client_traffics.inbound_id is a legacy single-inbound pointer that goes stale when an inbound is deleted and recreated: the email-keyed traffic row survives but references a missing inbound. Code that resolved the owning inbound from it broke several client operations.

- adjustTraffics: 'Start After First Use' (negative expiry) never converted to an absolute deadline on first traffic, so the countdown never started. Now resolves inbounds via the client_inbounds link and computes the new expiry once per email so multi-inbound clients stay consistent.

- GetClientInboundByEmail / GetClientInboundByTrafficID: fall back to client_inbounds when the pointer is dead, fixing reset traffic ('record not found'), client info, and Telegram set-tgId.

- autoRenewClients: resolve renew targets via client_inbounds so scheduled renews are not silently skipped.

- clients page: allow resetting a client with no inbound attachment (the backend already zeroes counters by email).

Add regression test for the delayed-start conversion under a stale inbound_id.

web/service/inbound_client_traffic_test.go

@@ -3,6 +3,7 @@ package service
 import (
 	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/mhsanaei/3x-ui/v3/database"
 	"github.com/mhsanaei/3x-ui/v3/database/model"
@@ -76,3 +77,74 @@ func TestAddClientTraffic_MatchesDespiteStaleInboundId(t *testing.T) {
 		t.Errorf("node-owned row should not be touched by local traffic: up=%d down=%d, want 0/0", node.Up, node.Down)
 	}
 }
+
+// TestAdjustTraffics_DelayedStartConvertsDespiteStaleInboundId covers "Start After
+// First Use": a delayed-start client carries a negative expiry (the duration) that
+// must convert to an absolute deadline on its first traffic tick. When the client's
+// email-keyed client_traffics row still points at a deleted inbound (stale inbound_id
+// after an inbound delete+recreate), the conversion used to resolve no inbound and
+// silently skip, leaving the client perpetually "not started". The fix resolves the
+// owning inbound via the client_inbounds link instead.
+func TestAdjustTraffics_DelayedStartConvertsDespiteStaleInboundId(t *testing.T) {
+	dbDir := t.TempDir()
+	t.Setenv("XUI_DB_FOLDER", dbDir)
+	if err := database.InitDB(filepath.Join(dbDir, "x-ui.db")); err != nil {
+		t.Fatalf("InitDB: %v", err)
+	}
+	t.Cleanup(func() { _ = database.CloseDB() })
+
+	db := database.GetDB()
+
+	const email = "delayed-user"
+	const uid = "ce8d33df-3a64-4f10-8f9b-91c3a8e0d001"
+	const sevenDays = int64(7 * 86400000)
+
+	client := model.Client{Email: email, ID: uid, Auth: uid, Enable: true, ExpiryTime: -sevenDays}
+	inbound := &model.Inbound{
+		Tag: "vless-delayed", Enable: true, Port: 45001, Protocol: model.VLESS,
+		StreamSettings: `{"network":"tcp","security":"reality"}`,
+		Settings:       clientsSettings(t, []model.Client{client}),
+	}
+	if err := db.Create(inbound).Error; err != nil {
+		t.Fatalf("create inbound: %v", err)
+	}
+
+	svc := InboundService{}
+	if err := svc.clientService.SyncInbound(db, inbound.Id, []model.Client{client}); err != nil {
+		t.Fatalf("SyncInbound: %v", err)
+	}
+
+	// The email-keyed traffic row survives an inbound delete+recreate pointing at a
+	// dead inbound id; client_inbounds still links the client to the live inbound.
+	if err := db.Create(&xray.ClientTraffic{InboundId: 9999, Email: email, Enable: true, ExpiryTime: -sevenDays}).Error; err != nil {
+		t.Fatalf("create stale traffic row: %v", err)
+	}
+
+	before := time.Now().UnixMilli()
+	if err := svc.addClientTraffic(db, []*xray.ClientTraffic{{Email: email, Up: 100, Down: 200}}); err != nil {
+		t.Fatalf("addClientTraffic: %v", err)
+	}
+
+	var row xray.ClientTraffic
+	if err := db.Model(xray.ClientTraffic{}).Where("email = ?", email).First(&row).Error; err != nil {
+		t.Fatalf("reload traffic row: %v", err)
+	}
+	if row.ExpiryTime <= 0 {
+		t.Fatalf("delayed-start expiry not converted: still %d (stale inbound_id skipped the conversion)", row.ExpiryTime)
+	}
+	if row.ExpiryTime < before+sevenDays-5000 || row.ExpiryTime > before+sevenDays+5000 {
+		t.Errorf("converted expiry = %d, want ~now+7d (%d)", row.ExpiryTime, before+sevenDays)
+	}
+
+	reloaded, err := svc.GetInbound(inbound.Id)
+	if err != nil {
+		t.Fatalf("GetInbound: %v", err)
+	}
+	cs, err := svc.GetClients(reloaded)
+	if err != nil {
+		t.Fatalf("GetClients: %v", err)
+	}
+	if len(cs) != 1 || cs[0].ExpiryTime <= 0 {
+		t.Errorf("inbound settings expiry not converted: %#v", cs)
+	}
+}