[CI] Add a lightweight PR size warning workflow

[utksh1]

Summary

Large PRs with generated artifacts are hard to review. Add a lightweight workflow or script that warns on unusually large diffs.

Scope

• Count changed files and total additions/deletions for PRs.
• Warn when generated paths such as playwright-report or test-results are included.
• Keep it advisory at first; do not fail CI unless maintainers choose to later.

Acceptance Criteria

• Workflow comments or logs a clear warning for oversized PRs.
• Generated report/result directories are called out by name.
• Documentation explains the threshold.

[CoderPrateek971]

Hi @utksh1, I am interested in doing this. Kindly assign this to me under GSSOC'26.

[Aayush20253534]

/assign gssoc

[CoderPrateek971]

Hello! @utksh1

I have created a Pull Request to address this issue: #388

What I did:
1.Added a lightweight, advisory GitHub Actions workflow that warns contributors about unusually large diffs or accidentally committed generated folders (playwright-report, test-results).
2.Ensured the script uses exit 0 so it only flags a warning and does not fail the CI build.
3.Updated CONTRIBUTING.md to document the 50 file / 1000 line threshold and explain how to fix the generated artifact warning.

Please let me know if you need any changes made to the PR. Thanks!