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

Database/QuestieDB.lua

@@ -7,6 +7,27 @@ QuestieDB.private = QuestieDB.private or {}
 ---@class QuestieDBPrivate
 local _QuestieDB = QuestieDB.private
 
+------------------------------------------------------------------------
+-- _MergeOverride: Merge override data into a result table.
+-- Override tables from QuestieLearner and AscensionDB use numeric keys
+-- ([1]=name, [7]=spawns, ...) while the result uses string keys
+-- ("name", "spawns", ...). This helper checks both formats:
+--   1. override[stringKey]  (string-keyed, e.g. from wotlkNPCFixes)
+--   2. override[intKey]     (numeric-keyed, e.g. from QuestieLearner / AscensionDB)
+--   3. rawdata[intKey]      (fallback to compiled DB)
+------------------------------------------------------------------------
+local function _MergeOverride(result, override, rawdata, keyMap)
+    for stringKey, intKey in pairs(keyMap) do
+        if override[stringKey] ~= nil then
+            result[stringKey] = override[stringKey]
+        elseif override[intKey] ~= nil then
+            result[stringKey] = override[intKey]
+        elseif rawdata then
+            result[stringKey] = rawdata[intKey]
+        end
+    end
+end
+
 -------------------------
 --Import modules.
 -------------------------
@@ -391,16 +412,10 @@ function QuestieDB:GetObject(objectId)
     }
 
     if override then
-        -- Prefer override data (corrections)
-        for stringKey, _ in pairs(QuestieDB.objectKeys) do
-            if override[stringKey] ~= nil then
-                obj[stringKey] = override[stringKey]
-            elseif rawdata then
-                -- Fallback to DB if override is partial
-                local intKey = QuestieDB.objectKeys[stringKey]
-                obj[stringKey] = rawdata[intKey]
-            end
-        end
+        -- Prefer override data (corrections); _MergeOverride checks both
+        -- string keys (override.name) and numeric keys (override[1]) so
+        -- AscensionDB and QuestieLearner numeric-key overrides are picked up.
+        _MergeOverride(obj, override, rawdata, QuestieDB.objectKeys)
     else
         -- Use standard DB data
         local stringKey, intKey = next(QuestieDB.objectKeys)
@@ -441,16 +456,9 @@ function QuestieDB:GetItem(itemId)
     }
 
     if override then
-        -- Prefer override data (corrections)
-        for stringKey, _ in pairs(QuestieDB.itemKeys) do
-            if override[stringKey] ~= nil then
-                item[stringKey] = override[stringKey]
-            elseif rawdata then
-                -- Fallback to DB if override is partial
-                local intKey = QuestieDB.itemKeys[stringKey]
-                item[stringKey] = rawdata[intKey]
-            end
-        end
+        -- Prefer override data (corrections); _MergeOverride handles both
+        -- string-keyed and numeric-keyed override formats.
+        _MergeOverride(item, override, rawdata, QuestieDB.itemKeys)
     else
         -- Use standard DB data
         local stringKey, intKey = next(QuestieDB.itemKeys)
@@ -1909,16 +1917,10 @@ function QuestieDB:GetNPC(npcId)
     }
 
     if override then
-        -- Prefer override data (corrections)
-        for stringKey, _ in pairs(npcKeys) do
-            if override[stringKey] ~= nil then
-                npc[stringKey] = override[stringKey]
-            elseif rawdata then
-                -- Fallback to DB if override is partial
-                local intKey = npcKeys[stringKey]
-                npc[stringKey] = rawdata[intKey]
-            end
-        end
+        -- Prefer override data (corrections); _MergeOverride handles both
+        -- string-keyed and numeric-keyed override formats. This is essential
+        -- for AscensionDB and QuestieLearner data which use numeric keys.
+        _MergeOverride(npc, override, rawdata, npcKeys)
     else
         -- Use standard DB data
         local stringKey, intKey = next(npcKeys)