Add argparse-based CLI for flexible path configuration and container compatibility

[anujonthemove]

This PR introduces an argparse-based Command-Line Interface (CLI) for grounded_sam2_local_demo.py to improve usability, flexibility, and compatibility especially for containerized environments.

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✅ Key Changes:

• Replaces hardcoded file paths with CLI arguments using Python’s argparse.

• Adds support for dynamically specifying:

  • Input image path
  • Text prompts
  • SAM2 checkpoint path and config
  • Grounding DINO config and checkpoint
  • Output directory
  • Thresholds and optional flags

• Includes inline comments to clarify argument purpose and usage.

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📌 How can this help:

• Improved Usability:
  Users no longer need to modify the script manually for different datasets or experiments.

• Container Compatibility:
  The original script's hardcoded paths made it difficult to run in Docker/Apptainer containers. The CLI allows dynamic path passing via mounted volumes or runtime parameters.

IMPORTANT NOTE:

This PR is depends on: #101