chore: update version to 2.0.1 and enhance Classic functionality with dynamic field discovery

sharepoint/assets/ExpiryIndicatorClassic.js

@@ -15,6 +15,27 @@
     return '';
   }
 
+  function discoverExpiryField() {
+    var id = listId(null);
+    if (!id) { return ''; }
+    try {
+      var xhr = new XMLHttpRequest();
+      xhr.open('GET', listUrl(id) +
+        '/fields?$select=InternalName,ClientSideComponentId', false);
+      xhr.setRequestHeader('Accept', 'application/json;odata=verbose');
+      xhr.setRequestHeader('OData-Version', '3.0');
+      xhr.send(null);
+      if (xhr.status < 200 || xhr.status >= 300) { return ''; }
+      var data = JSON.parse(xhr.responseText || '{}');
+      var fields = data.d ? data.d.results : (data.value || []);
+      for (var index = 0; index < fields.length; index++) {
+        var componentId = String(fields[index].ClientSideComponentId || '').replace(/[{}]/g, '').toLowerCase();
+        if (componentId === FIELD_CUSTOMIZER_ID) { return fields[index].InternalName; }
+      }
+    } catch (ignore) { }
+    return '';
+  }
+
   function pageContext() {
     return window._spPageContextInfo || {};
   }
@@ -473,7 +494,7 @@
   function register() {
     if (window.SPClientTemplates && SPClientTemplates.TemplateManager) {
       var overrides = { OnPostRender: render };
-      var expiryField = configuredExpiryField();
+      var expiryField = configuredExpiryField() || discoverExpiryField();
       if (expiryField) {
         overrides.Templates = { Fields: {} };
         overrides.Templates.Fields[expiryField] = {