Fix Ender Dragon damage, End portal transition, and End Poem crash

Dragon melee damage: reassign sub-entity IDs to be sequential from
the parent entity ID in ServerLevel::entityAdded(), so the client's
offset-based ID calculation matches the server. Previously the server's
smallId pool allocated non-sequential IDs, causing melee attacks to
target entity IDs the server didn't recognize.

End portal transition: ensure the player entity is always added to the
new level when transitioning from The End, not just for non-End
dimensions. The addEntity call was previously gated behind a
lastDimension != 1 check that also excluded it from End exits.

End Poem crash: bounds-check the WIN_GAME event's player index before
accessing localplayers[], with a fallback to prevent null dereference
when the server sends an out-of-range index.

Minecraft.Client/Common/UI/UIScene_EndPoem.cpp

@@ -50,13 +50,18 @@ UIScene_EndPoem::UIScene_EndPoem(int iPad, void *initData, UILayer *parentLayer)
 	Minecraft *pMinecraft = Minecraft::GetInstance();
 
 	wstring playerName = L"";
-	if(pMinecraft->localplayers[ui.GetWinUserIndex()] != nullptr)
+	unsigned int winIdx = ui.GetWinUserIndex();
+	if(winIdx < XUSER_MAX_COUNT && pMinecraft->localplayers[winIdx] != nullptr)
 	{
-		playerName = escapeXML( pMinecraft->localplayers[ui.GetWinUserIndex()]->getDisplayName() );
+		playerName = escapeXML( pMinecraft->localplayers[winIdx]->getDisplayName() );
+	}
+	else if(pMinecraft->localplayers[ProfileManager.GetPrimaryPad()] != nullptr)
+	{
+		playerName = escapeXML( pMinecraft->localplayers[ProfileManager.GetPrimaryPad()]->getDisplayName() );
 	}
 	else
 	{
-		playerName = escapeXML( pMinecraft->localplayers[ProfileManager.GetPrimaryPad()]->getDisplayName() );
+		playerName = L"Player";
 	}
 	noNoiseString = replaceAll(noNoiseString,L"{*PLAYER*}",playerName);
 

Minecraft.Client/PlayerConnection.cpp

@@ -816,9 +816,7 @@ void PlayerConnection::handleInteract(shared_ptr<InteractPacket> packet)
 		{
 			if ((target->GetType() == eTYPE_ITEMENTITY) || (target->GetType() == eTYPE_EXPERIENCEORB) || (target->GetType() == eTYPE_ARROW) || target == player)
 			{
-				//disconnect("Attempting to attack an invalid entity");
-				//server.warn("Player " + player.getName() + " tried to attack an invalid entity");
-				return;
+					return;
 			}
 			player->attack(target);
 		}

Minecraft.Client/PlayerList.cpp

@@ -951,15 +951,16 @@ void PlayerList::repositionAcrossDimension(shared_ptr<Entity> entity, int lastDi
 		addPlayerToReceiving(player);
 	}
 
-	if (lastDimension != 1)
+	xt = static_cast<double>(Mth::clamp(static_cast<int>(xt), -Level::MAX_LEVEL_SIZE + 128, Level::MAX_LEVEL_SIZE - 128));
+	zt = static_cast<double>(Mth::clamp(static_cast<int>(zt), -Level::MAX_LEVEL_SIZE + 128, Level::MAX_LEVEL_SIZE - 128));
+	if (entity->isAlive())
 	{
-		xt = static_cast<double>(Mth::clamp(static_cast<int>(xt), -Level::MAX_LEVEL_SIZE + 128, Level::MAX_LEVEL_SIZE - 128));
-		zt = static_cast<double>(Mth::clamp(static_cast<int>(zt), -Level::MAX_LEVEL_SIZE + 128, Level::MAX_LEVEL_SIZE - 128));
-		if (entity->isAlive())
+		newLevel->addEntity(entity);
+		entity->moveTo(xt, entity->y, zt, entity->yRot, entity->xRot);
+		newLevel->tick(entity, false);
+		// Portal forcing only for non-End exits (End exits go to spawn, not a portal)
+		if (lastDimension != 1)
 		{
-			newLevel->addEntity(entity);
-			entity->moveTo(xt, entity->y, zt, entity->yRot, entity->xRot);
-			newLevel->tick(entity, false);
 			newLevel->cache->autoCreate = true;
 			newLevel->getPortalForcer()->force(entity, xOriginal, yOriginal, zOriginal, yRotOriginal);
 			newLevel->cache->autoCreate = false;

Minecraft.Client/ServerLevel.cpp

@@ -1052,9 +1052,14 @@ void ServerLevel::entityAdded(shared_ptr<Entity> e)
 	vector<shared_ptr<Entity> > *es = e->getSubEntities();
 	if (es)
 	{
+		// Reassign sub-entity IDs to be sequential from the parent's ID.
+		// The client assumes this layout when it applies an offset in handleAddMob.
+		int offset = 1;
 		for(auto& i : *es)
 		{
+			i->entityId = e->entityId + offset;
 			entitiesById.emplace(i->entityId, i);
+			offset++;
 		}
 	}
 	entityAddedExtra(e);	// 4J added

Minecraft.World/EnderDragon.cpp

@@ -1118,15 +1118,6 @@ bool EnderDragon::hurt(shared_ptr<MultiEntityMobPart> MultiEntityMobPart, Damage
 		damage = damage / 4 + 1;
 	}
 
-	//float rot1 = yRot * PI / 180;
-	//float ss1 = sin(rot1);
-	//float cc1 = cos(rot1);
-
-	//xTarget = x + ss1 * 5 + (random->nextFloat() - 0.5f) * 2;
-	//yTarget = y + random->nextFloat() * 3 + 1;
-	//zTarget = z - cc1 * 5 + (random->nextFloat() - 0.5f) * 2;
-	//attackTarget = nullptr;
-
 	if ( source->getEntity() != nullptr && source->getEntity()->instanceof(eTYPE_PLAYER) || source->isExplosion() )
 	{
 		int healthBefore = getHealth();