fix(items): retry render when slot reads nil for a previously occupied slot

The event-level retry only protected the ITEM_SLOT_UPDATE broadcast, but
ItemSlot:Update() reads GetContainerItemInfo live on every call and is
invoked from many paths (OnShow → ReloadAllItemSlots, AddItemSlot,
BAG_UPDATE_TYPE, search updates). On a laggy server those live reads
flash slots empty. Add a shared retry queue at the slot-render level so
a slot with self.hasItem set will defer rather than draw nil; cap at
RENDER_RETRY_MAX so a genuinely emptied slot still resolves within ~3s.

Bagnon/components/item.lua

@@ -248,6 +248,37 @@ end
 --[[ Update Methods ]]
 --
 
+-- Shared retry queue for slots whose live read returned nil for a previously
+-- occupied slot — almost always a server lag race where item data hasn't
+-- arrived yet. Retrying renders the correct texture instead of flashing empty.
+local RENDER_RETRY_INTERVAL = 0.1
+local RENDER_RETRY_MAX = 30  -- ~3s cap so a genuine empty still resolves
+local pendingSlots = {}
+local slotRetryFrame = CreateFrame('Frame')
+slotRetryFrame.elapsed = 0
+slotRetryFrame:Hide()
+slotRetryFrame:SetScript('OnUpdate', function(self, elapsed)
+	self.elapsed = self.elapsed + elapsed
+	if self.elapsed < RENDER_RETRY_INTERVAL then return end
+	self.elapsed = 0
+	local q = pendingSlots
+	pendingSlots = {}
+	for slot in pairs(q) do
+		if slot:IsVisible() then
+			slot:Update()
+		end
+	end
+	if not next(pendingSlots) then
+		self:Hide()
+	end
+end)
+
+local function scheduleSlotRetry(slot)
+	pendingSlots[slot] = true
+	slotRetryFrame.elapsed = 0
+	slotRetryFrame:Show()
+end
+
 
 -- Update the texture, lock status, and other information about an item
 function ItemSlot:Update()
@@ -255,6 +286,17 @@ function ItemSlot:Update()
 
 	local texture, count, locked, quality, readable, lootable, link = self:GetItemSlotInfo()
 
+	-- Lag race: the slot was occupied a moment ago but the server hasn't
+	-- delivered item data yet. Defer rendering so the slot doesn't flash empty.
+	if self.hasItem and (not link) then
+		self.renderRetries = (self.renderRetries or 0) + 1
+		if self.renderRetries < RENDER_RETRY_MAX then
+			scheduleSlotRetry(self)
+			return
+		end
+	end
+	self.renderRetries = nil
+
 	self:SetItem(link)
 	self:SetTexture(texture)
 	self:SetCount(count)