feat(editor): open terrain format integrated into export workflow

- File > Export Open Format (.wot/.whm) menu item for standalone export
- Every zone export (Ctrl+S, Export Zone) now also writes .wot/.whm
  alongside the ADT/WDT — dual format output
- Export package now contains: ADT + WDT + WOT + WHM + JSON files
- Both Blizzard-compatible (for existing servers) and open format
  (for wowee-native loading and redistribution)

tools/editor/editor_app.cpp

@@ -2,6 +2,7 @@
 #include "adt_writer.hpp"
 #include "zone_manifest.hpp"
 #include "content_pack.hpp"
+#include "wowee_terrain.hpp"
 #include "core/coordinates.hpp"
 #include "rendering/vk_context.hpp"
 #include "pipeline/adt_loader.hpp"
@@ -730,6 +731,11 @@ void EditorApp::exportZone(const std::string& outputDir) {
         objectPlacer_.saveToFile(objPath);
     }
 
+    // Export open terrain format alongside ADT
+    std::string openBase = base + "/" + loadedMap_ + "_" +
+                           std::to_string(loadedTileX_) + "_" + std::to_string(loadedTileY_);
+    WoweeTerrain::exportOpen(terrain_, openBase, loadedTileX_, loadedTileY_);
+
     // Write zone info README
     {
         std::ofstream readme(base + "/README.txt");
@@ -780,6 +786,16 @@ void EditorApp::exportContentPack(const std::string& destPath) {
         showToast("Failed to create content pack");
 }
 
+void EditorApp::exportOpenFormat(const std::string& basePath) {
+    if (!terrain_.isLoaded()) return;
+    std::string base = basePath + "/" + loadedMap_ + "/" + loadedMap_ + "_" +
+                       std::to_string(loadedTileX_) + "_" + std::to_string(loadedTileY_);
+    if (WoweeTerrain::exportOpen(terrain_, base, loadedTileX_, loadedTileY_))
+        showToast("Open format exported (.wot + .whm)");
+    else
+        showToast("Open format export failed");
+}
+
 void EditorApp::quickSave() {
     if (!terrain_.isLoaded()) return;
     std::string dir = lastSavePath_.empty() ? "output" : lastSavePath_;

tools/editor/editor_app.hpp

@@ -37,6 +37,7 @@ public:
     void exportZone(const std::string& outputDir);
     void quickSave();
     void exportContentPack(const std::string& destPath);
+    void exportOpenFormat(const std::string& basePath);
 
     void requestQuit();
     void resetCamera();

tools/editor/editor_ui.cpp

@@ -158,6 +158,8 @@ void EditorUI::renderMenuBar(EditorApp& app) {
                 app.quickSave();
             if (ImGui::MenuItem("Export Zone...", nullptr, false, app.hasTerrainLoaded()))
                 showSaveDialog_ = true;
+            if (ImGui::MenuItem("Export Open Format (.wot/.whm)", nullptr, false, app.hasTerrainLoaded()))
+                app.exportOpenFormat("output");
             if (ImGui::MenuItem("Export Content Pack (.wcp)", nullptr, false, app.hasTerrainLoaded())) {
                 std::string wcpPath = "output/" + app.getLoadedMap() + ".wcp";
                 app.exportContentPack(wcpPath);