fix: real-time minimap pins + defensive GetAchievementNumCriteria shim

1. _InvalidateSpawnListsForNPC was setting objective.AlreadySpawned = nil,
   causing _DetermineIconsToDraw to crash on nil-index when trying to draw
   updated pins. The xpcall wrapper in UpdateObjectiveNotes swallowed the
   error silently, so no icons appeared.

   Fix: unload existing map/minimap icons explicitly, then set
   AlreadySpawned = {} (empty table) instead of nil. Also clear
   hasRegisteredTooltips so tooltips refresh.

2. Added GetAchievementNumCriteria defensive shim for Ascension servers
   with incomplete achievement databases. Returns 0 for invalid IDs
   instead of hard-erroring in Blizzard's WorldMapFrame.

Modules/QuestieCompat.lua

@@ -604,6 +604,24 @@ QuestieCompat.IsAchievementCompleted = QuestieCompat.IsAchievementCompleted or f
     return completed or false
 end
 
+--- GetAchievementNumCriteria Shim
+-- Ascension and some custom servers have incomplete achievement databases.
+-- Blizzard's WorldMapFrame calls this with invalid IDs, causing a hard error.
+-- Wrap the global to return 0 for invalid inputs so the UI doesn't break.
+do
+    local _original = GetAchievementNumCriteria
+    GetAchievementNumCriteria = function(achievementID)
+        if type(achievementID) ~= "number" or achievementID <= 0 then
+            return 0
+        end
+        local ok, numCriteria = pcall(_original, achievementID)
+        if ok then
+            return numCriteria or 0
+        end
+        return 0
+    end
+end
+
 --- LibUIDropDownMenu Shim
 QuestieCompat.LibUIDropDownMenu = QuestieCompat.LibUIDropDownMenu or {}
 QuestieCompat.LibUIDropDownMenu.UIDropDownMenu_Menu_NewSize = function()