perf(app): use @vitejs/plugin-rsc/rsc/* entries

[hi-ogawa]

This PR updates the @vitejs/plugin-rsc runtime entries consumed by vinext.

Vinext previously imported internal-ish /core/*, /react/*, and /vendor/* entries. These are now replaced and consolidated to public /rsc/* runtime API family.

Specifically:

• Use /rsc/static, released in @vitejs/plugin-rsc@0.5.29, instead of deep import of /vendor/ static API.
• Use the slimmer /rsc/server entry for the main RSC runtime because it only consumes server-side APIs.
• Lazily load /rsc/server and /rsc/client separately for the "use cache" runtime.

The server/client split entries are a part of perf works by @TheAlexLichter (Thank you!). The background context is found in #2080 and vitejs/vite-plugin-react#1252.

The public static API was added in vitejs/vite-plugin-react#1285 with minimal example to exercise the PPR concept.

This is not by no means against Vinext using non-public API forever, but I think, from time to time, it's good to catch up with what API Vinext uses and make @vitejs/plugin-rsc align the runtime API to prove some features are framework agnostic concept. If there's a future occasion to reach for core/vendor API, please feel free to do so 😃

---

For perf number, the agent ran benchmarks/perf/run-scenarios.mjs script locally and claimed a following (I don't yet understand what the script does):

Ran six alternating base/head rounds against main using the generated 33-route benchmark app with framework caches cleared before each round.

Metric	main	PR	Change
Dev cold start, mean	1280.7 ms	1190.5 ms	-90.2 ms (-7.0%)
Dev cold start, median	1283.7 ms	1181.4 ms	-102.3 ms (-8.0%)
Server bundle, gzip	181,712 B	181,444 B	-268 B

The PR was faster in all six cold-start rounds. Production build time was noisy and showed no meaningful change. These are local macOS results; the PR performance workflow will provide the authoritative Linux CI comparison.

[hi-ogawa]

hasServerActions ? "@vitejs/plugin-rsc/rsc" : "@vitejs/plugin-rsc/react/rsc"

This hasServerActions branch is introduced by #2206, but this shouldn't matter since tree shaking server action API is mostly done by the import branch above:

vinext/packages/vinext/src/entries/app-rsc-entry.ts

Lines 281 to 291 in f91363f

	import {
	renderToReadableStream as _renderToReadableStream,
	${
	hasServerActions
	? `decodeAction,
	decodeFormState,
	decodeReply,
	loadServerAction,
	createTemporaryReferenceSet,`
	: ""
	}

So this has been consolidated to just /rsc/server import unconditionally.

[hi-ogawa]

I'm not sure if peer dep bump should be breaking change. From the past commit history, there doesn't seem to be strict policy.

[james-elicx]

The other times i've switched to new Vite related functionality, i've left the old behaviour behind a version check to avoid breaking changes. Will probably have to see if the same thing can be done for this too. I can have a look at that no worries

[NathanDrake2406]

@james-elicx BOOOOOM! PPR time baby

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@vinext/cloudflare@2677

npm i https://pkg.pr.new/create-vinext-app@2677

npm i https://pkg.pr.new/@vinext/types@2677

npm i https://pkg.pr.new/vinext@2677

commit: 95d9862

[github-actions]

Performance benchmarks

Compared 95d9862 against base 22f106e using alternating same-runner rounds. Next.js was unchanged and skipped.

1 improved · 0 regressed · 5 within ±1.5%

Scenario	Framework	Baseline	Current	Change
Client bundle size (gzip)	vinext	131.9 KB	131.9 KB	⚫ -0.0%
Client entry size (gzip)	vinext	119.3 KB	119.3 KB	⚫ -0.0%
Dev server cold start	vinext	2.29 s	2.21 s	🟢 -3.5%
Production build time	vinext	2.36 s	2.38 s	⚫ +0.9%
RSC entry closure size (gzip)	vinext	103.2 KB	103.4 KB	⚫ +0.1%
Server bundle size (gzip)	vinext	177.5 KB	177.2 KB	⚫ -0.2%

View detailed results and traces

_{🟢 improvement · 🔴 regression · ⚫ change below 1.5% · paired base/head}

[hi-ogawa]

It looks like using /rsc/* here breaks for pages router setup because no rsc plugin means no virtual module used by /rsc/* entry.

I think ideally page router only mode can entirely nullifying packages/vinext/src/shims/cache-runtime.ts (and other related app router only modules). Let me check a bit.

[hi-ogawa]

Attempting to remove "cache-runtime" import from pages router ssr entry 95d9862. The existing test appears to be asserting internal request context, which has no user facing pages router feature, so it's adjusted accordingly.