feat: Enhance MegaMenu with localization, caching, and new properties

- Added localization support for loading states, empty navigation, and submenu actions in both German and English.
- Introduced new properties in IMenuItem for description, openInNewWindow, and external links.
- Updated SPTermStorePickerService to handle cache versioning and language-specific caching.
- Implemented a new MegaMenuCore service for handling term properties, cache management, and navigation URL resolution.
- Refactored TaxonomyNavigationService to build menu hierarchy and filter hidden terms.
- Added automated tests for MegaMenu core functionalities and static asset validation.
- Removed unused ItemDictionary service.
- Created a comprehensive ToDo document outlining the implementation status and future tasks.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "mega-menu",
-  "version": "2.1.0",
+  "version": "2.2.0",
   "private": true,
   "main": "lib/index.js",
   "engines": {
@@ -10,8 +10,8 @@
     "build:classic": "powershell -NoProfile -ExecutionPolicy Bypass -File .\\build-classic.ps1",
     "build": "npm run build:classic && gulp bundle",
     "clean": "gulp clean",
-    "test": "gulp test",
-    "package": "npm run build:classic && gulp clean && gulp bundle --ship && gulp package-solution --ship"
+    "test": "tsc -p tests/tsconfig.json && node temp/tests/tests/MegaMenuCore.test.js && node --check classic/megamenu-services-standalone.js && node --check classic/megamenu-classic.js && node tests/validate-static-assets.js",
+    "package": "npm test && npm run build:classic && gulp clean && gulp bundle --ship && gulp package-solution --ship"
   },
   "dependencies": {
     "@microsoft/decorators": "~1.4.1",