fix: align RSS GUID fallback logic across tracking, filtering, and idempotency

The GUID fallback computation now consistently guards against missing title/pubDate fields in all three locations (tracking at line 117-121, filtering at line 238-241, and idempotency at line 295-298). This prevents mismatches where items lacking both guid and link would generate empty strings in tracking but 'undefined' strings in idempotency keys, causing duplicate processing on subsequent poll cycles.

Author: cursoragent

apps/sim/lib/webhooks/polling/rss.ts

@@ -292,7 +292,10 @@ async function processRssItems(
 
   for (const item of items) {
     try {
-      const itemGuid = item.guid || item.link || `${item.title}-${item.pubDate}`
+      const itemGuid =
+        item.guid ||
+        item.link ||
+        (item.title && item.pubDate ? `${item.title}-${item.pubDate}` : '')
 
       await pollingIdempotency.executeWithIdempotency(
         'rss',