fix: guard unavailable quest draw thread

Modules/Quest/AvailableQuests.lua

@@ -282,6 +282,10 @@ end
 _DrawAvailableQuest = function(questId)
     NewThread(function()
         local quest = QuestieDB.GetQuest(questId)
+        if not quest then
+            Questie:Debug(Questie.DEBUG_LEARNER, "[AvailableQuests] Skipping unavailable quest during draw:", questId)
+            return
+        end
         if (not quest.tagInfoWasCached) then
             QuestieDB.GetQuestTagInfo(questId) -- cache to load in the tooltip
 

Tests/QuestieAvailableQuests_spec.lua

@@ -0,0 +1,15 @@
+local function read(path)
+    local f = assert(io.open(path, "r"), "cannot open " .. path)
+    local c = f:read("*a")
+    f:close()
+    return c
+end
+
+describe("Questie available quests guard", function()
+    it("skips unavailable quests before touching tagInfoWasCached", function()
+        local content = read("Modules/Quest/AvailableQuests.lua")
+        assert.is_true(content:find("if not quest then", 1, true) ~= nil)
+        assert.is_true(content:find("Skipping unavailable quest during draw", 1, true) ~= nil)
+        assert.is_true(content:find("quest.tagInfoWasCached = true", 1, true) ~= nil)
+    end)
+end)