Add Current Navigation Application Customizer

- Created a new SPFx Application Customizer for current navigation.
- Implemented core functionality to fetch and render navigation items from a SharePoint term set.
- Added styles for the navigation component using SCSS.
- Included localization support for English and German languages.
- Developed unit tests for core navigation functionalities.
- Configured TypeScript and TSLint settings for the project.
- Added validation scripts for static assets and package configuration.

config/package-solution.json

@@ -0,0 +1,11 @@
+{
+  "$schema": "https://developer.microsoft.com/json-schemas/spfx-build/package-solution.schema.json",
+  "solution": {
+    "name": "current-navigation-client-side-solution",
+    "id": "bb8f9af5-b318-4111-8401-ce189cfe1b1a",
+    "version": "1.0.0.0",
+    "includeClientSideAssets": true,
+    "skipFeatureDeployment": true
+  },
+  "paths": { "zippedPackage": "solution/current-navigation.sppkg" }
+}