chore(cleanup): purge runtime logs, obsolete scripts, and raw PDFs while preserving sample NEET/JEE testing datasets

backend/worker.py

@@ -4,7 +4,7 @@ Active Tasks:
   - generate_daily_study_plans: Runs daily at 5:00 AM IST via Celery Beat
 
 Deferred (Phase 2 — AI LLM):
-  - process_pdf_test: PDF → LLM → Questions pipeline (stubbed in pdf_parser.py)
+  - process_pdf_test: Automated PDF → LLM → Questions pipeline
 """
 import os
 from datetime import datetime