fix(tests & jsonl): Improve test structure and refine JSONL parsing for incomplete data

ts/classes.jsonldata.ts

@@ -96,8 +96,9 @@ export class JsonlDataProcessor<T> {
               },
               finalFunction: async (streamToolsArg) => {
                 console.log(`finished processing ${totalRecordsCounter} records.`);
-                if (!nextRest) return;
-                JSON.parse(nextRest);
+                if (nextRest) {
+                  JSON.parse(nextRest);
+                };
                 done.resolve();
               },
             })