perf: fix memory leaks in the edge runtime in dev

[feedthejim]

This PR fixes a memory leak when using next dev where on HMR, we would always retain the memory associated with the old VM instance, leading to pretty egregious usage of RAM after only a few edits.

The leak itself comes from methods like setTimeout and setInterval capturing the context in which they were called and somehow never releasing, even if the timeout happened, when running in a Node.js vm. This is probably a Node.js bug.

The fix consists of taking ownership of all timeouts and clearing them ourselves manually at the end of each VM lifecycle.

Tested manually:

• hello world Next.js app with edge runtime
• triggered hmr 10 times
• memory usage
  • base: 400MB
  • before: 800MB
  • after: 400MB

[ijjk]

Stats from current PR

Default Build

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
buildDuration	10.4s	10.5s	N/A
buildDurationCached	6.1s	6.1s	N/A
nodeModulesSize	174 MB	174 MB	⚠️ +17.4 kB
nextStartRea..uration (ms)	519ms	511ms	N/A

Client Bundles (main, webpack)

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
199-HASH.js gzip	27.9 kB	27.9 kB	N/A
3f784ff6-HASH.js gzip	53.2 kB	53.2 kB	N/A
99.HASH.js gzip	182 B	182 B	✓
framework-HASH.js gzip	45.5 kB	45.5 kB	✓
main-app-HASH.js gzip	254 B	251 B	N/A
main-HASH.js gzip	33 kB	33 kB	N/A
webpack-HASH.js gzip	1.75 kB	1.75 kB	N/A
Overall change	45.7 kB	45.7 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
_app-HASH.js gzip	206 B	205 B	N/A
_error-HASH.js gzip	182 B	180 B	N/A
amp-HASH.js gzip	506 B	505 B	N/A
css-HASH.js gzip	322 B	323 B	N/A
dynamic-HASH.js gzip	2.59 kB	2.59 kB	✓
edge-ssr-HASH.js gzip	260 B	259 B	N/A
head-HASH.js gzip	350 B	350 B	✓
hooks-HASH.js gzip	369 B	369 B	✓
image-HASH.js gzip	4.38 kB	4.38 kB	N/A
index-HASH.js gzip	256 B	256 B	✓
link-HASH.js gzip	2.67 kB	2.67 kB	N/A
routerDirect..HASH.js gzip	316 B	318 B	N/A
script-HASH.js gzip	385 B	384 B	N/A
withRouter-HASH.js gzip	319 B	319 B	✓
1afbb74e6ecf..834.css gzip	106 B	106 B	✓
Overall change	3.99 kB	3.99 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
_buildManifest.js gzip	484 B	482 B	N/A
Overall change	0 B	0 B	✓

Rendered Page Sizes

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
index.html gzip	528 B	529 B	N/A
link.html gzip	541 B	541 B	✓
withRouter.html gzip	523 B	524 B	N/A
Overall change	541 B	541 B	✓

Edge SSR bundle Size

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
edge-ssr.js gzip	95.8 kB	95.8 kB	N/A
page.js gzip	158 kB	158 kB	N/A
Overall change	0 B	0 B	✓

Middleware size

	vercel/next.js canary	vercel/next.js feedthejim/edge-memory-leaks	Change
middleware-b..fest.js gzip	625 B	622 B	N/A
middleware-r..fest.js gzip	150 B	151 B	N/A
middleware.js gzip	22.9 kB	22.9 kB	N/A
edge-runtime..pack.js gzip	1.92 kB	1.92 kB	✓
Overall change	1.92 kB	1.92 kB	✓

Commit: 8da2fc2