v1.6.3-unreleased: Sunstrider zone fixes, QuestieLearner icon preservation, migration, and Busted test suite

Code changes (13 files, +916/-171):
- ZoneDB integration: GetZoneId() converts uiMapId→areaId via ZoneDB reverse lookup
- MIN_CONFIDENCE_PINS reduced to 1 for Ascension (incomplete NPC DBs)
- QuestieLearner icon preservation: objective Icon passed to RegisterObjectiveTooltip
- InjectLearnedData zone migration: converts old uiMapId spawn keys to areaId
- areaId passed through all LearnNPC call sites (OnMouseoverUnit, OnQuestDetail,
  OnQuestComplete, OnQuestAccepted, OnQuestTurnedIn, OnGossipShow)
- Compat/Compat.lua: C_Map.GetPlayerMapPosition UiMapData support
- Compat/HBD.lua: Sunstrider mapData aliases and fallback loading
- Sunstrider arrow fix (QuestieArrow.lua), resolved pin rendering (QuestieMap.lua)
- _MergeOverride helper for string/numeric key compatibility
- Northshire Valley UiMapData registration

Testing infrastructure:
- .busted config pointing to tests/ directory
- Tests/wow_api_mock.lua: WoW API mocks (ZoneDB, C_Map, QuestLogCache, etc.)
- Tests/QuestieLearner_spec.lua: 12 tests covering coordinate scaling, spell cast
  learning, zone migration (NPC/objects), icon preservation, settings defaults,
  and LearnNPC spawn zone tracking
- selene.toml + wow_classic.yml: linter configuration

Documentation:
- Makefile with test/lint/ci targets
- sunstrider-coordinate-collection.md: coordinate data reference
- sunstrider-pin-fix.md: root cause analysis and fix documentation

Modules/QuestieCoordinates.lua

@@ -111,6 +111,21 @@ end
 
 ---@return table<{x: number, y: number}>, number | nil
 function QuestieCoords.GetPlayerMapPosition()
+    -- If the world map is open, use the map currently being displayed instead of
+    -- GetBestMapForUnit("player"). On legacy clients our compat shim may call
+    -- SetMapToCurrentZone()/SetMapByID() while resolving the player's map, which
+    -- fights the open world map and causes the title/coordinate text to flicker.
+    if WorldMapFrame and WorldMapFrame:IsVisible() then
+        local currentMapId = WorldMapFrame:GetMapID()
+        if currentMapId and GetPlayerMapPosition then
+            local pos = GetPlayerMapPosition(currentMapId, "player")
+            if pos and pos.x and pos.y then
+                pos.uiMapID = currentMapId
+                return pos, currentMapId
+            end
+        end
+    end
+
     local mapID = GetBestMapForUnit("player")
     if (not mapID) then
         return nil, nil
@@ -142,7 +157,19 @@ function QuestieCoords:ResetMinimapText()
 end
 
 function QuestieCoords:ResetMapText()
-    GetMapTitleText():SetText(WORLD_MAP);
+    local mapTitleText = GetMapTitleText()
+    if not mapTitleText then return end
+
+    local currentMapId = WorldMapFrame and WorldMapFrame.GetMapID and WorldMapFrame:GetMapID()
+    if currentMapId then
+        local info = C_Map.GetMapInfo(currentMapId)
+        if info and info.name then
+            mapTitleText:SetText(info.name)
+            return
+        end
+    end
+
+    mapTitleText:SetText(WORLD_MAP);
 end
 
 function QuestieCoords:ResetMiniWorldMapText()