Fix collection manager JavaScript errors after attribute naming changes

- Update collection manager to use data-collection-id instead of data-content-id
- Add safety checks to prevent undefined Map access in addItemControls
- Add validation in editor to only initialize collections with valid collection IDs
- Resolves TypeError and missing attribute errors in frontend collection management

lib/package-lock.json

@@ -311,6 +311,7 @@
       "integrity": "sha512-GVsDdsbJzzy4S/v3dqWPJ7EfvZJfCHiDqe80IyrF59LYuP+e6U1LJoUqeuqRbwAWoMNoXivMNeNAOf5E22VA1w==",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "bin": {
         "rollup": "dist/bin/rollup"
       },

lib/src/core/editor.js

@@ -79,7 +79,9 @@ export class InsertrEditor {
     
     initializeCollection(meta) {
         const collectionManager = new CollectionManager(meta, this.apiClient, this.auth);
-        collectionManager.initialize();
+        if (collectionManager.collectionId) {
+            collectionManager.initialize();
+        }
     }
     
     addClickHandler(element, meta) {

lib/src/ui/collection-manager.js

@@ -18,9 +18,9 @@ export class CollectionManager {
         this.auth = auth;
         
         // Extract collection ID from container
-        this.collectionId = this.container.getAttribute('data-content-id');
+        this.collectionId = this.container.getAttribute('data-collection-id');
         if (!this.collectionId) {
-            console.error('❌ Collection container missing data-content-id attribute');
+            console.error('❌ Collection container missing data-collection-id attribute');
             return;
         }
         
@@ -331,7 +331,7 @@ export class CollectionManager {
      * Add management controls to an item (remove, reorder)
      */
     addItemControls(itemElement, index) {
-        if (this.itemControls.has(itemElement)) return; // Already has controls
+        if (!this.itemControls || this.itemControls.has(itemElement)) return; // Already has controls or not initialized
         
         const controls = document.createElement('div');
         controls.className = 'insertr-item-controls';