Add ExpiryIndicator binding functionality and UI enhancements

- Introduced a new button in the portal settings to bind the ExpiryIndicator to existing date fields.
- Added a modal dialog for binding configuration, including fields for web URL, list title, and internal field name.
- Enhanced the ExpiryIndicator panel to include options for loading and saving site collection defaults.
- Updated the JavaScript functions to handle binding logic and validation for the ExpiryIndicator.
- Improved the user interface for better usability and clarity in the portal settings page.

config/package-solution.json

@@ -3,7 +3,7 @@
   "solution": {
     "name": "portal-settings-client-side-solution",
     "id": "1c98e32d-bb7b-43b7-9625-074d6e4ea286",
-    "version": "2.0.0.0",
+    "version": "2.1.0.0",
     "includeClientSideAssets": true,
     "skipFeatureDeployment": false,
     "features": [
@@ -11,7 +11,7 @@
         "title": "Portal Settings",
         "description": "Provisioniert die zentrale Settings-Seite fuer aktive Portal-Erweiterungen.",
         "id": "57bd9daf-48f9-49e2-aebd-11b15a0b5e93",
-        "version": "2.0.0.0",
+        "version": "2.1.0.0",
         "assets": {
           "elementManifests": [
             "elements-v2.xml"