Add personal contribution language stats

[andrecollar]

Summary

Adds an optional personal_contributions=true mode for the Top Languages card.
This mode calculates language usage from additions in commits authored by the requested user, instead of using repository-wide language totals. It is useful for users whose work happens mostly in organization repositories they do not own.

New query parameters

• personal_contributions=true
• orgs=org1,org2
• personal_pages=2
• personal_limit=40

Notes

• Requires a self-hosted instance with a GitHub token for private organization repositories.
• Counts authored commit additions, not current line ownership via git blame.
• Uses personal_limit to keep serverless execution bounded.
• For private organization repositories, classic tokens need repo and read:org; SAML/SSO organizations require token authorization.

Tests

npx.cmd prettier --check readme.md
npx.cmd eslint --max-warnings 0 src\fetchers\personal-contribution-languages.js api\top-langs.js tests\fetchPersonalContributionLanguages.test.js 
npm.cmd test -- --runTestsByPath tests\top-langs.test.js tests\fetchTopLanguages.test.js      tests\fetchPersonalContributionLanguages.test.js

[vercel]

@andrecollar is attempting to deploy a commit to the github readme stats Team on Vercel.

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[martin-mfg]

Thanks for the PR!

Maintenance of this project has moved to https://github.com/stats-organization/github-stats-extended (see here for context). It would be great if you could adapt your code changes to that repository and then open a PR there.

Also, please use this file from GitHub for the language detection logic. This will ensure consistency with GitHub's language detection and is a comprehensive list of possible languages.