Add quickstart instructions for running CI checks locally

[aviralgarg05]

Summary

Document how to run the same checks as CI (lint, format check, tests) so new contributors can validate changes before opening a PR.

Suggested changes

• Update README.md (or create CONTRIBUTING.md section) with a short "Local CI" snippet:
  • poetry install --with dev
  • poetry check
  • poetry run ruff check .
  • poetry run ruff format --check .
  • poetry run pytest
• Mention Python 3.10+ requirement and Poetry usage.

Why this is beginner-friendly

• Pure documentation change with copy/paste commands.
• Helps first-time contributors avoid CI failures.

Acceptance criteria

• New section exists with the above commands and context.
• Commands are accurate for the current setup.
• Spelling/formatting is clean.