Fix post-hearthstone asset gaps and add quest tracker interactivity

Hearthstone post-teleport fix:
- Expand same-map hearthstone precache from 5x5 to 9x9 tiles so workers
  have more tiles parsed before the player arrives at the bind point
- After same-map teleport arrival, enqueue the full load-radius tile grid
  (17x17 = 289 tiles) at the new position so background workers immediately
  start loading all WMOs/M2s visible from the new location

Quest tracker improvements:
- Clicking a quest in the tracker now opens the Quest Log (L)
- Remove NoInputs flag so the tracker window receives mouse events
- Show only tracked quests in tracker; fall back to all quests if none tracked
- Add Track/Untrack button in Quest Log details panel
- Abandoning a quest automatically untracks it
- Track state stored in GameHandler::trackedQuestIds_ (per-session)

src/ui/quest_log_screen.cpp

@@ -373,11 +373,17 @@ void QuestLogScreen::render(game::GameHandler& gameHandler) {
                     }
                 }
 
-                // Abandon button
+                // Track / Abandon buttons
+                ImGui::Separator();
+                bool isTracked = gameHandler.isQuestTracked(sel.questId);
+                if (ImGui::Button(isTracked ? "Untrack" : "Track", ImVec2(100.0f, 0.0f))) {
+                    gameHandler.setQuestTracked(sel.questId, !isTracked);
+                }
                 if (!sel.complete) {
-                    ImGui::Separator();
+                    ImGui::SameLine();
                     if (ImGui::Button("Abandon Quest", ImVec2(150.0f, 0.0f))) {
                         gameHandler.abandonQuest(sel.questId);
+                        gameHandler.setQuestTracked(sel.questId, false);
                         selectedIndex = -1;
                     }
                 }