Support multiple pages directories for linting

[JacobLey]

Monorepos may contain multiple NextJS apps, but linting occurs at top-level so all directories must be declared.

Declaring multiple directories via an Array allows loading all to generate a full list of potential URLs.

Updated schema and tests. Also optimized some of the fs.*Sync requests that can add up to lots of blocking lookups.

Feature

• Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
• Related issues linked using fixes #number
• Integration tests added
• Documentation added
• Telemetry added. In case of a feature if it's used or not.

Closes: #27223

[ijjk]

Stats from current PR

Default Build (Decrease detected ✓)

General

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
buildDuration	12.9s	13.9s	⚠️ +968ms
buildDurationCached	3s	2.9s	-68ms
nodeModulesSize	49.5 MB	49.5 MB	✓

Page Load Tests Overall decrease ⚠️

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
/ failed reqs	0	0	✓
/ total time (seconds)	2.149	2.05	-0.1
/ avg req/sec	1163.39	1219.44	+56.05
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.165	1.236	⚠️ +0.07
/error-in-render avg req/sec	2146.52	2023.39	⚠️ -123.13

Client Bundles (main, webpack, commons)

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
359.HASH.js gzip	2.96 kB	2.96 kB	✓
745.HASH.js gzip	180 B	180 B	✓
framework-HASH.js gzip	42.2 kB	42.2 kB	✓
main-HASH.js gzip	20.9 kB	20.9 kB	✓
webpack-HASH.js gzip	1.53 kB	1.53 kB	✓
Overall change	67.8 kB	67.8 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
polyfills-HASH.js gzip	31.1 kB	31.1 kB	✓
Overall change	31.1 kB	31.1 kB	✓

Client Pages

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
_app-HASH.js gzip	803 B	803 B	✓
_error-HASH.js gzip	3.06 kB	3.06 kB	✓
amp-HASH.js gzip	554 B	554 B	✓
css-HASH.js gzip	329 B	329 B	✓
dynamic-HASH.js gzip	2.52 kB	2.52 kB	✓
head-HASH.js gzip	2.28 kB	2.28 kB	✓
hooks-HASH.js gzip	903 B	903 B	✓
image-HASH.js gzip	5.61 kB	5.61 kB	✓
index-HASH.js gzip	261 B	261 B	✓
link-HASH.js gzip	1.66 kB	1.66 kB	✓
routerDirect..HASH.js gzip	319 B	319 B	✓
script-HASH.js gzip	387 B	387 B	✓
withRouter-HASH.js gzip	320 B	320 B	✓
bb14e60e810b..30f.css gzip	125 B	125 B	✓
Overall change	19.1 kB	19.1 kB	✓

Client Build Manifests

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
_buildManifest.js gzip	490 B	490 B	✓
Overall change	490 B	490 B	✓

Rendered Page Sizes

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
index.html gzip	531 B	531 B	✓
link.html gzip	544 B	544 B	✓
withRouter.html gzip	525 B	525 B	✓
Overall change	1.6 kB	1.6 kB	✓

---

Webpack 4 Mode (Increase detected ⚠️)

General

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
buildDuration	10.4s	10.3s	-124ms
buildDurationCached	3.8s	3.8s	-27ms
nodeModulesSize	49.5 MB	49.5 MB	✓

Page Load Tests Overall increase ✓

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
/ failed reqs	0	0	✓
/ total time (seconds)	1.99	2.021	⚠️ +0.03
/ avg req/sec	1256.2	1237.07	⚠️ -19.13
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.118	1.095	-0.02
/error-in-render avg req/sec	2235.29	2282.13	+46.84

Client Bundles (main, webpack, commons)

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
17.HASH.js gzip	2.98 kB	2.98 kB	✓
18.HASH.js gzip	185 B	185 B	✓
677f882d2ed8..HASH.js gzip	13.7 kB	13.7 kB	✓
framework.HASH.js gzip	41.9 kB	41.9 kB	✓
main-HASH.js gzip	8.4 kB	8.4 kB	✓
webpack-HASH.js gzip	1.22 kB	1.22 kB	✓
Overall change	68.4 kB	68.4 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
polyfills-HASH.js gzip	31.3 kB	31.3 kB	✓
Overall change	31.3 kB	31.3 kB	✓

Client Pages

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
_app-HASH.js gzip	791 B	791 B	✓
_error-HASH.js gzip	3.76 kB	3.76 kB	✓
amp-HASH.js gzip	552 B	552 B	✓
css-HASH.js gzip	333 B	333 B	✓
dynamic-HASH.js gzip	2.71 kB	2.71 kB	✓
head-HASH.js gzip	2.97 kB	2.97 kB	✓
hooks-HASH.js gzip	911 B	911 B	✓
index-HASH.js gzip	231 B	231 B	✓
link-HASH.js gzip	1.64 kB	1.64 kB	✓
routerDirect..HASH.js gzip	298 B	298 B	✓
script-HASH.js gzip	3.02 kB	3.02 kB	✓
withRouter-HASH.js gzip	294 B	294 B	✓
e025d2764813..52f.css gzip	125 B	125 B	✓
Overall change	17.6 kB	17.6 kB	✓

Client Build Manifests

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
_buildManifest.js gzip	500 B	500 B	✓
Overall change	500 B	500 B	✓

Rendered Page Sizes

	vercel/next.js canary	JacobLey/next.js monorepoLint	Change
index.html gzip	577 B	577 B	✓
link.html gzip	587 B	587 B	✓
withRouter.html gzip	569 B	569 B	✓
Overall change	1.73 kB	1.73 kB	✓

Commit: 5ac28a5

[ijjk]

Added change and tests look good, thanks for the PR!