feat: client detects WOB buildings and JSON DBCs from custom zones

- TerrainManager now checks for .wob files before loading WMO buildings
  (searches custom_zones/buildings/ and output/MapName/buildings/)
- AssetManager::loadDBC() scans custom_zones/*/data/ for JSON DBC
  overrides exported by the editor
- WOB detection logs when found (full WOB→WMOModel conversion pending)
- JSON DBC detection logs when found (full JSON→DBCFile loading pending)

Client open format support status:
- WOT/WHM terrain: FULL (loads and renders)
- PNG textures: FULL (override system)
- WOM models: FULL (loads and renders)
- zone.json: DETECTION (CustomZoneDiscovery scans)
- WOB buildings: DETECTION (found, conversion pending)
- JSON DBC: DETECTION (found, loading pending)

src/rendering/terrain_manager.cpp

@@ -10,6 +10,7 @@
 #include "core/coordinates.hpp"
 #include "pipeline/wowee_terrain_loader.hpp"
 #include "pipeline/wowee_model.hpp"
+#include "pipeline/wowee_building.hpp"
 #include "core/memory_monitor.hpp"
 #include "core/profiler.hpp"
 #include "pipeline/asset_manager.hpp"
@@ -594,6 +595,22 @@ std::shared_ptr<PendingTile> TerrainManager::prepareTile(int x, int y) {
             if (placement.nameId >= pending->terrain.wmoNames.size()) continue;
 
             const std::string& wmoPath = pending->terrain.wmoNames[placement.nameId];
+
+            // Check for WOB open format first (custom zone buildings)
+            {
+                std::string wobBase = wmoPath;
+                auto wobDot = wobBase.rfind('.');
+                if (wobDot != std::string::npos) wobBase = wobBase.substr(0, wobDot);
+                std::replace(wobBase.begin(), wobBase.end(), '\\', '/');
+                std::vector<std::string> wobPrefixes = {"custom_zones/buildings/", "output/" + mapName + "/buildings/"};
+                for (const auto& prefix : wobPrefixes) {
+                    if (pipeline::WoweeBuildingLoader::exists(prefix + wobBase)) {
+                        LOG_INFO("WOB building found: ", prefix + wobBase, " (loading not yet implemented)");
+                        break;
+                    }
+                }
+            }
+
             std::vector<uint8_t> wmoData = assetManager->readFile(wmoPath);
             if (wmoData.empty()) continue;