Fix dynamic transform ssr:false case for pages router with ESM

[huozhi]

We introduced a new transform (#56761) for non-SSR next/dynamic to always "weakly" linked the non-SSR module, so that in app router we can still enter the module to discover the server actions, but in edge runtime we also won't bundle it in the server bundle.

For app router since we bundle all it works well. But when you import a ESM in pages router it doesn't work as it become the path of "commonjs require (ESM path)"

Solution

Leveraging the esm option for next swc loader, which means if we really prefer the esm asset for bundling, in pages router it's false and we won't apply the new transform.

Closes #59235
Closes NEXT-1788

[ijjk]

Stats from current PR

Default Build

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
buildDuration	10.2s	10.3s	N/A
buildDurationCached	5.8s	6.5s	⚠️ +642ms
nodeModulesSize	199 MB	199 MB	⚠️ +1.34 kB
nextStartRea..uration (ms)	422ms	418ms	N/A

Client Bundles (main, webpack)

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
199-HASH.js gzip	30.7 kB	30.7 kB	N/A
3f784ff6-HASH.js gzip	53.3 kB	53.3 kB	✓
494.HASH.js gzip	180 B	181 B	N/A
framework-HASH.js gzip	45.2 kB	45.2 kB	✓
main-app-HASH.js gzip	241 B	239 B	N/A
main-HASH.js gzip	31.7 kB	31.7 kB	N/A
webpack-HASH.js gzip	1.7 kB	1.7 kB	✓
Overall change	100 kB	100 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
_app-HASH.js gzip	194 B	195 B	N/A
_error-HASH.js gzip	182 B	181 B	N/A
amp-HASH.js gzip	501 B	503 B	N/A
css-HASH.js gzip	322 B	323 B	N/A
dynamic-HASH.js gzip	2.5 kB	2.5 kB	✓
edge-ssr-HASH.js gzip	253 B	255 B	N/A
head-HASH.js gzip	348 B	347 B	N/A
hooks-HASH.js gzip	369 B	368 B	N/A
image-HASH.js gzip	4.27 kB	4.27 kB	N/A
index-HASH.js gzip	256 B	256 B	✓
link-HASH.js gzip	2.61 kB	2.6 kB	N/A
routerDirect..HASH.js gzip	311 B	311 B	✓
script-HASH.js gzip	384 B	383 B	N/A
withRouter-HASH.js gzip	307 B	308 B	N/A
1afbb74e6ecf..834.css gzip	106 B	106 B	✓
Overall change	3.17 kB	3.17 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
_buildManifest.js gzip	484 B	483 B	N/A
Overall change	0 B	0 B	✓

Rendered Page Sizes

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
index.html gzip	528 B	527 B	N/A
link.html gzip	538 B	540 B	N/A
withRouter.html gzip	524 B	522 B	N/A
Overall change	0 B	0 B	✓

Edge SSR bundle Size

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
edge-ssr.js gzip	92.6 kB	92.7 kB	N/A
page.js gzip	145 kB	145 kB	N/A
Overall change	0 B	0 B	✓

Middleware size

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
middleware-b..fest.js gzip	628 B	626 B	N/A
middleware-r..fest.js gzip	150 B	151 B	N/A
middleware.js gzip	35.7 kB	35.7 kB	N/A
edge-runtime..pack.js gzip	1.92 kB	1.92 kB	✓
Overall change	1.92 kB	1.92 kB	✓

Next Runtimes

	vercel/next.js canary	vercel/next.js fix/dynamic-transform	Change
app-page-exp...dev.js gzip	168 kB	168 kB	✓
app-page-exp..prod.js gzip	93.8 kB	93.8 kB	✓
app-page-tur..prod.js gzip	94.5 kB	94.5 kB	✓
app-page-tur..prod.js gzip	89.1 kB	89.1 kB	✓
app-page.run...dev.js gzip	138 kB	138 kB	✓
app-page.run..prod.js gzip	88.4 kB	88.4 kB	✓
app-route-ex...dev.js gzip	24.2 kB	24.2 kB	✓
app-route-ex..prod.js gzip	16.8 kB	16.8 kB	✓
app-route-tu..prod.js gzip	16.9 kB	16.9 kB	✓
app-route-tu..prod.js gzip	16.4 kB	16.4 kB	✓
app-route.ru...dev.js gzip	23.6 kB	23.6 kB	✓
app-route.ru..prod.js gzip	16.4 kB	16.4 kB	✓
pages-api-tu..prod.js gzip	9.37 kB	9.37 kB	✓
pages-api.ru...dev.js gzip	9.64 kB	9.64 kB	✓
pages-api.ru..prod.js gzip	9.37 kB	9.37 kB	✓
pages-turbo...prod.js gzip	21.9 kB	21.9 kB	✓
pages.runtim...dev.js gzip	22.6 kB	22.6 kB	✓
pages.runtim..prod.js gzip	21.9 kB	21.9 kB	✓
server.runti..prod.js gzip	49.3 kB	49.3 kB	✓
Overall change	930 kB	930 kB	✓

Commit: bddc066

[timneutkens]

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