fix(quest/learner): draw turn-in '?' for in-log quests; learn turn-in NPC

Reverts the previous approach of stripping char.complete (which mutated
completed-quest data). Correct rule: a quest in the player's log is active
and should show its turn-in location regardless of the completed flag.

- AddFinisher now trusts the live quest log: if the quest is in
  currentQuestlog and not failed, the '?' finisher draws regardless of the
  (possibly stale, e.g. prior-prestige) char.complete flag. No completion
  data is modified. Reverts the AcceptQuest and QUEST_QUERY_COMPLETE strips.

- Learner: OnTargetChanged now learns quest-giver/turn-in NPC spawns
  (it previously only cached the GUID), so targeting a turn-in NPC records
  its location. OnQuestComplete/OnQuestTurnedIn fall back to the 'target'
  unit when the 'npc' gossip unit is already cleared, so the finisher NPC
  is reliably learned on turn-in.

selene 0 errors; busted 145 successes / same 7 pre-existing failures.

CHANGELOG.md

@@ -32,7 +32,8 @@
 
 ### Bug Fixes
 
-- **[Quest - Re-accepted (Prestige) Quest Stuck "Complete", No Turn-In '?']** A quest completed in a previous Ascension prestige stays in `Questie.db.char.complete`; when re-accepted it is active again in the log, but the stale completion flag was never cleared. `AddFinisher` only draws the turn-in `?` when `not char.complete[questId]`, so the finisher was suppressed and the quest mislabelled "(Complete)" with stale objective text, even while standing at the turn-in NPC. An active in-log quest is now kept out of `char.complete` in two places: it is cleared in `QuestieQuest:AcceptQuest` on accept, and the asynchronous `QUEST_QUERY_COMPLETE` handler now also strips any quest currently in the player's log (so the server's completed list can't re-flag a re-accepted quest). The turn-in `?` and normal objective tracking are restored.
+- **[Quest - Turn-In '?' Missing For Quests In The Log]** A quest in the player's log is active and not yet turned in, so its turn-in `?` finisher should always be drawable — but `AddFinisher` also required `not char.complete[questId]`, so a quest completed in a previous Ascension prestige (still flagged in `char.complete`) and then re-accepted had its finisher suppressed while standing at the turn-in NPC. `AddFinisher` now trusts the live quest log: if the quest is in `currentQuestlog` and not failed, the finisher draws regardless of the (possibly stale) completed flag. No quest-completion data is modified.
+- **[Learner - Turn-In/Quest NPC Not Learned When Targeted]** In learner mode the turn-in NPC's location wasn't always recorded, so its `?` finisher couldn't draw. `OnTargetChanged` only cached the GUID and never called `LearnNPC`; it now learns the spawn of quest-giver/turn-in NPCs (gated like `OnMouseoverUnit`), so simply targeting a turn-in NPC records its position. The `QUEST_COMPLETE`/`QUEST_TURNED_IN` handlers also fall back to the `target` unit when the `npc` gossip unit is already cleared, so the finisher NPC is reliably learned on turn-in.
 - **[Map - Completed Quests Still Shown As Available]** (#7) The server's completed-quest list is delivered asynchronously (the `QUEST_QUERY_COMPLETE` event), often after available quests were first drawn — so quests that were actually already complete kept showing as available `!` until something forced a redraw (e.g. `/reload`). Questie now recalculates available quests once `char.complete` is populated by that event, removing the completed ones. This also clears the "already completed" subset of the false-available pins reported in #8.
 - **[Map - Available '!' Lingered On Minimap For Accepted Quests]** (#9) When a quest was accepted, its available `!` icon could remain on the minimap until a `/reload`. `QuestieMap:UnloadQuestFramesByDataType` unloaded the frame but left its name in the frame registry and `_G`, so the minimap icon was not fully torn down. It now removes the registry/global reference as well, so the available icon is cleared immediately on accept for both the map and minimap.