Add CLI-driven text input/output for word cloud generation and document enhancement roadmap

[Copilot]

The project still required passing text by editing source code directly, which blocked basic automation and reuse. This PR adds runtime input/output controls and captures near-term enhancement opportunities discovered during repo analysis.

• What changed

  • Reworked show_wordcloud.py into a CLI entrypoint with main().
  • Added argument parsing for:
    • --text (inline text input)
    • --text-file (UTF-8 file input)
    • --output (custom output PNG path)
  • Added input resolution logic with mutual exclusivity validation for --text and --text-file.
  • Preserved backward compatibility by falling back to the existing default sample text when no input flags are provided.
  • Closed figure resources after save to avoid handle leakage in repeated runs.

• Documentation updates

  • Updated README usage to reflect default, inline, and file-based input modes.
  • Marked the “pass text as input argument” task as completed.
  • Added a concise “Possible Enhancements” backlog (cloud upload, styling flags, CI expansion, tests, API mode).

• Example usage

  python3 show_wordcloud.py --text "GitHub Actions GitHub Packages Protected branches" --output mycloud.png
  python3 show_wordcloud.py --text-file /path/to/input.txt --output /path/to/wordcloud.png