Fix(Converting_Roman_to_Integer): Fix crashes, add syntax validation, CLI/interactive mode, unit tests & docs

[Prayas340]

Description

Refactored and enhanced Converting_Roman_to_Integer with robust syntax validation, bidirectional Roman/Integer conversion, interactive and CLI support, unit tests, and updated documentation.

Fixes #475

• Issue_no: Fix IndexError, input validation, and enhance Converting_Roman_to_Integer #475
• Not applicable

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Documentation Update

Project

• Your Project Name: Converting Roman to Integer

• Short Description: A robust CLI and interactive tool to convert Roman numerals to integers and integers to Roman numerals with full syntax validation and unit tests.

Checklist:

• I have named my files and folder according to this project's guidelines.
• My code follows the style guidelines of this project (PEP 8, type hints, docstrings).
• I have commented on my code, particularly in hard-to-understand areas.
• I have created a helpful and easy to understand README.md, according to the given README_TEMPLATE.md.
• My changes do not produce any warnings.