Implement CLI Entry Point

[fedem-p]

1. Implement CLI Entry Point

Description: Create the main command-line interface in photosort/main.py to accept user input and trigger program actions.
Tasks:

• Read the README carefully to understand CLI requirements and options.
• Design CLI argument parsing (e.g., input folder, dry run, scan/report).
• Connect CLI to core modules.
• Write unit tests for argument parsing and main entry logic.
• Run ./lint.sh to ensure code quality.