fix: resolve video download CORS via host_permissions, unify records in activities.json, and add exporter_job_info.json

dashboard/viewer_template.html

@@ -263,17 +263,22 @@
     async function init() {
       if (!ARCHIVE_DATA) {
         try {
-          const res = await fetch('manifest.json');
+          const res = await fetch('activities.json');
           if (res.ok) {
             ARCHIVE_DATA = await res.json();
           }
         } catch (e) {
-          console.warn('Could not fetch manifest.json, checking global', e);
+          try {
+            const fallbackRes = await fetch('manifest.json');
+            if (fallbackRes.ok) ARCHIVE_DATA = await fallbackRes.json();
+          } catch (e2) {
+            console.warn('Could not fetch activities.json or manifest.json', e2);
+          }
         }
       }
 
       if (!ARCHIVE_DATA || !ARCHIVE_DATA.activities) {
-        document.getElementById('feedGrid').innerHTML = '<div class="empty-state">No activities found in manifest.json. Ensure manifest.json is in the same directory.</div>';
+        document.getElementById('feedGrid').innerHTML = '<div class="empty-state">No activities found in activities.json. Ensure activities.json is in the same directory.</div>';
         return;
       }