fix(kb): store filename with .txt extension for connector documents

Connector documents (e.g. Fireflies transcripts) have titles without
file extensions. The DB stored the raw title as filename, but the
processing pipeline extracts file extension from filename to determine
the parser. On retry/reprocess, this caused "Unsupported file type"
errors with the document title treated as the extension.

Now stores processingFilename (which includes .txt) instead of the
raw title, consistent with what was actually uploaded to storage.

Author: waleedlatif1

apps/sim/lib/knowledge/connectors/sync-engine.ts

@@ -742,7 +742,7 @@ async function addDocument(
       await tx.insert(document).values({
         id: documentId,
         knowledgeBaseId,
-        filename: extDoc.title,
+        filename: processingFilename,
         fileUrl,
         fileSize: contentBuffer.length,
         mimeType: 'text/plain',
@@ -841,7 +841,7 @@ async function updateDocument(
       await tx
         .update(document)
         .set({
-          filename: extDoc.title,
+          filename: processingFilename,
           fileUrl,
           fileSize: contentBuffer.length,
           contentHash: extDoc.contentHash,