Support multiple deploy template list URLs with cross-list dedupe

Add Settings UI to configure many Portainer-format template catalogs (not just one), merge them on fetch, drop duplicates by image/stack/title, and show source counts on the Deploy view.

libs/templateDeploy.js

@@ -1,6 +1,7 @@
 // Import dependencies first (ES6 imports must be at top)
 import { closeAllModals, showStatusIndicator, hideStatusIndicator, updateStatusIndicator, showAlert } from './uiUtils.js';
 import notificationManager from './notifications.js';
+import { fetchMergedTemplates, getTemplateListUrls } from '../client/templateLists.js';
 
 // DOM Elements - Lazy loaded (initialized when modal opens)
 let templateList = null;
@@ -62,22 +63,35 @@ function initTemplateDeployer() {
   setupFormSubmitListener();
 }
 
-// Fetch templates from the URL
+// Fetch templates from all configured list URLs (multi-source, de-duplicated)
 async function fetchTemplates() {
     // Ensure template deployer is initialized before fetching
     initTemplateDeployer();
     
     try {
-        const response = await fetch('https://raw.githubusercontent.com/Lissy93/portainer-templates/main/templates.json');
-        if (!response.ok) {
-            throw new Error(`HTTP error! status: ${response.status}`);
-        }
-        const data = await response.json();
-        templates = data.templates || []; // Update global templates
+        const urls = getTemplateListUrls();
+        const result = await fetchMergedTemplates(urls);
+        templates = result.templates || [];
         displayTemplateList(templates);
+        const st = result.stats || {};
+        if (st.duplicates > 0) {
+            console.log(
+                `[INFO] Templates: ${st.unique} unique from ${st.sources} list(s), removed ${st.duplicates} duplicate(s)`
+            );
+        }
+        if (st.errors?.length && !templates.length) {
+            showAlert('danger', `Failed to load templates from ${st.errors.length} list(s).`);
+        } else if (st.errors?.length) {
+            showAlert(
+                'warning',
+                `Loaded ${templates.length} templates; ${st.errors.length} list(s) failed to fetch.`
+            );
+        }
+        return result;
     } catch (error) {
         console.error('[ERROR] Failed to fetch templates:', error.message);
         showAlert('danger', 'Failed to load templates.');
+        return null;
     }
 }