feat(ci): label pull requests by changed paths

[ryzrr]

Summary
Adds PR Labeling on new PRs

What kind of change does this PR introduce?
Feat - CI

Did you add tests for your changes?
no

Does this PR introduce a breaking change?
no

If relevant, what needs to be documented once your changes are merged or what have you already documented?
no

Use of AI
at few places

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
webpack-doc-kit	Ready	Preview	Aug 8, 2026 12:15pm

[github-actions]

⚡ Lighthouse report

Audited the Vercel preview deployment: https://webpack-doc-mtvhdan7e-openjs.vercel.app

URL	Performance	Accessibility	Best Practices	SEO	Report
/	🟢 92	🟢 96	🟢 100	🟢 100	🔗
/about	🟢 98	🟢 97	🟢 100	🟢 100	🔗
/about/sponsors	🟠 84	🟢 95	🟢 100	🟢 100	🔗
/blog	🟢 99	🟢 96	🟢 100	🟢 100	🔗
/blog/posts/2026-02-04-roadmap-2026	🟢 98	🟢 93	🟢 100	🟢 100	🔗
/guides/getting-started	🟢 96	🟢 97	🟢 100	🟢 100	🔗
/docs/api/options	🔴 66	🟢 96	🟢 100	🟢 100	n/a
/docs/loaders/css-loader	🟢 98	🟢 97	🟢 100	🟠 83	🔗

Scores are advisory (warn at 90); they do not fail the build. See .lighthouserc.json.