feat: Add retry logic with countdown in post_downloader.py
- Implemented 5-attempt retry with customizable 5-second countdown in
post_downloader.pyforfetch_and_detect_files. - Added line-by-line countdown logging for each retry delay second.
- Introduced
retry_delay_secondsvariable for flexible retry timing. - Enhanced error handling for HTTP 429 and exceptions with detailed retry logs.
- Maintained existing thread termination checks for consistency.