Improve .gitignore with relevant Python and environment ignores

[Jasmine-Sardana]

Description

What is this PR

• Bug fix
• Addition of a new feature
• Other

Why is this PR needed?

The current .gitignore file is missing some commonly ignored Python environment and tooling artifacts (e.g., .env, .venv/, .mypy_cache/, .ruff_cache/). Adding these ensures that unnecessary or sensitive files are not tracked and keeps the repository clean.

What does this PR do?

• Adds relevant ignore rules for:
  • Python virtual environments (.venv/, .env)
  • Type checking and linting caches (.mypy_cache/, .ruff_cache/)
  • Python packaging (__pypackages__/)
• Preserves all existing project-specific .gitignore rules
• Avoids adding unnecessary or unrelated entries to keep the file concise

References

Closes #6

How has this PR been tested?

• Verified locally using git status to ensure ignored files (e.g., .venv/, .env, __pycache__/) are not tracked
• Confirmed that existing tracked files remain unaffected

Is this a breaking change?

No. This PR only updates the .gitignore file and does not affect any runtime functionality.

Does this PR require an update to the documentation?

No. This change only affects repository configuration.

Checklist:

• The code has been tested locally
• Tests have been added to cover all new functionality (unit & integration)
• The documentation has been updated to reflect any changes
• The code has been formatted with pre-commit