fix(DB/Quest): Show objective marker on Zaxxis mobs (#27569)

e2e/README.md

@@ -156,6 +156,7 @@ go test -tags=e2e ./local/... -count=1 -v -timeout 30m -parallel 1
 | quests/lifecycle | STAY_ALIVE fail on death; status after save/relog | P1 | covered (`TestAC_26549_*`) | #26549 |
 | quests/escort | find spawned unit; follow-NPC despawns on logout | P2 | covered (`TestAC_24450_*`) | #24450 |
 | quests/frostmourne | scrying-orb vision runs; Muradin leaves the cavern and despawns; quest 12478 COMPLETE | P2 | covered (`TestAC_25760_*`); dialogue order and duplicate line `blocked-harness` (no monster-say capture) | #25760 |
+| quests/objectives | a mob that drops a quest item advertises it, so the client shows the objective on hover (`creature_questitem` -> `SMSG_CREATURE_QUERY_RESPONSE.questItems`) | P2 | covered (`TestAC_27553_*`), decoding the response through a raw packet hook since the harness has no dispatch case for it | #27553 |
 | items/equip | visible-item slot after EquipEntry; additem; survives relog | P2 | covered | — |
 | protocol/session | pos; item/quest load; money save/relog | P1 | covered; GM vis persist `blocked-harness` (extra_flags after relog) | #25793 |
 | protocol/teleport | cross-map; named; GoCreatureID | P1 | covered | — |

e2e/suites/quests/objectives/questitem_marker_e2e_test.go

@@ -0,0 +1,120 @@
+//go:build e2e
+
+package objectives_test
+
+import (
+	"encoding/binary"
+	"sync"
+	"testing"
+	"time"
+
+	_ "github.com/go-sql-driver/mysql"
+
+	"github.com/azerothcore/AzerothGhost/e2e/e2eharness"
+	"github.com/azerothcore/azerothcore-wotlk/e2e/internal/meta"
+)
+
+// SMSG_CREATURE_QUERY_RESPONSE. The harness has no dispatch case for this opcode,
+// so the payload is read through a raw packet hook: WorldClient.handlePacket calls
+// invokePacketHooks for every opcode before its own switch, so unparsed packets are
+// still observable. Same approach as suites/spells/immunity.
+const smsgCreatureQueryResponse uint16 = 0x0061
+
+// Issue: https://github.com/azerothcore/azerothcore-wotlk/issues/27553
+//
+// Quests 10262 and 10308 ask for Zaxxis Insignia (29209). Hovering a mob that drops
+// it showed no objective, because that marker is not a server-side flag: creatures
+// have no equivalent of GameObject::ActivateToQuest, and the client learns which
+// quest items a creature carries from the questItems array in
+// SMSG_CREATURE_QUERY_RESPONSE, filled from creature_questitem.
+//
+// This asks the server for each dropping creature and asserts the insignia is among
+// the six advertised items. On unfixed data all six are zero.
+func TestAC_27553_ZaxxisMobsAdvertiseQuestItem(t *testing.T) {
+	meta.Begin(t, meta.TestMeta{
+		Tags:     []string{"short", "quests", "issue", "serial"},
+		Runtime:  "short",
+		Issue:    27553,
+		Category: "quests/objectives",
+	})
+
+	const itemZaxxisInsignia = uint32(29209)
+	mobs := []struct {
+		entry uint32
+		name  string
+	}{
+		{18875, "ZaxxisRaider"},
+		{19641, "WarpRaiderNesaad"},
+		{19642, "ZaxxisStalker"},
+	}
+
+	// CMSG_CREATURE_QUERY is STATUS_LOGGEDIN and the handler ignores the guid it is
+	// given, so the bot can ask from wherever it logs in. No travel or spawn needed.
+	bot := e2eharness.NewSolo(t, e2eharness.ScenarioOpts{Prefix: "QItem", Level: 80})
+
+	for _, m := range mobs {
+		t.Run(m.name, func(t *testing.T) {
+			items := creatureQuestItems(t, bot, m.entry)
+			for _, it := range items {
+				if it == itemZaxxisInsignia {
+					t.Logf("OK %s (%d) advertises item %d", m.name, m.entry, itemZaxxisInsignia)
+					return
+				}
+			}
+			e2eharness.Assertf(t,
+				"%s (%d) advertises %v; expected %d among them, without which the client shows no objective on hover",
+				m.name, m.entry, items, itemZaxxisInsignia)
+		})
+	}
+
+	bot.AssertWorldAlive(t)
+}
+
+// creatureQuestItems asks the server about one creature and returns the six
+// questItems slots. The response ends with questItems[6] followed by movementId,
+// so they are the last 28 bytes less that trailing uint32.
+func creatureQuestItems(t *testing.T, bot *e2eharness.ScenarioBot, entry uint32) []uint32 {
+	t.Helper()
+
+	var (
+		mu   sync.Mutex
+		got  []uint32
+		once sync.Once
+	)
+	done := make(chan struct{})
+
+	cancel := bot.World.AddPacketHook(func(opcode uint16, data []byte) {
+		// A creature the server does not know answers with entry|0x80000000 and no
+		// body, which the length check drops.
+		if opcode != smsgCreatureQueryResponse || len(data) < 32 {
+			return
+		}
+		if binary.LittleEndian.Uint32(data[:4]) != entry {
+			return
+		}
+		tail := data[len(data)-28:]
+		out := make([]uint32, 6)
+		for i := range out {
+			out[i] = binary.LittleEndian.Uint32(tail[i*4 : i*4+4])
+		}
+		mu.Lock()
+		got = out
+		mu.Unlock()
+		once.Do(func() { close(done) })
+	})
+	defer cancel()
+
+	if err := bot.World.CreatureQuery(entry, 0); err != nil {
+		e2eharness.HarnessFailf(t, "CreatureQuery(%d): %v", entry, err)
+	}
+
+	select {
+	case <-done:
+	case <-time.After(15 * time.Second):
+		e2eharness.HarnessFailf(t, "no creature query response for entry %d within 15s", entry)
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	return got
+}