- Add tag count validation (max 10) in both CLI and uploader layers
- CLI: exit with error if tags > 10, prompt user to reduce
- Uploader: truncate to first 10 with warning as fallback
- Prevents infinite loop when XHS UI rejects excess tags
- Add check_original_declaration() to auto-check original content
declaration before publishing (video and note modes)
- Gracefully skips if the option is not present on the page
