test(cloudflare): prove browser reuse of warmed RSC variants

[james-elicx]

Stacked on #3029.

Summary

Extend the deployed Workers cache E2E to prove the remaining browser request shapes in the RSC CDN prewarming acceptance criteria:

• router.prefetch() reuses the prewarmed loading-shell entry, then router.push() reuses the prewarmed full RSC entry
• an actual <Link prefetch> request to a non-cacheable dynamic route remains no-store / CF-Cache-Status: BYPASS

The same deployed test already proves Link loading-shell/full reuse from multiple source routes, full-prefetch reuse without a second request, and direct soft-navigation reuse.

Scope

Test-only. No runtime, cache, routing, deploy, or development-mode behavior changes.

Validation

• vp check tests/e2e/cloudflare-workers/rsc-prewarm.spec.ts
• local Playwright discovery/guard run for the deployed-only spec (1 expected skip without an HTTPS Worker)

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/@vinext/cloudflare@3030

npm i https://pkg.pr.new/create-vinext-app@3030

npm i https://pkg.pr.new/@vinext/types@3030

npm i https://pkg.pr.new/vinext@3030

commit: c615ff1

[github-actions]

Example	Preview	Production	Original
app-router-cloudflare	preview	production
pages-router-cloudflare	preview	production
app-router-playground	preview	production	original
realworld-api-rest	preview	production
nextra-docs-template	preview	production
benchmarks	preview	production
hackernews	preview	production	original
workers-cache	preview	production
web	preview	production

[github-actions]

Performance benchmarks

Compared c615ff1 against base 2d668a6 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	142.1 KB	142.2 KB	⚫ +0.0%
Client entry size (gzip)	vinext	129.4 KB	129.5 KB	⚫ +0.0%
Dev server cold start	vinext	3.66 s	3.70 s	⚫ +1.2%
Production build time	vinext	4.37 s	4.29 s	🟢 -2.0%
RSC entry closure size (gzip)	vinext	116.0 KB	116.0 KB	⚫ +0.0%
Server bundle size (gzip)	vinext	197.5 KB	197.5 KB	⚫ +0.0%

View detailed results and traces

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

[james-elicx]

Superseded by consolidated PR #3040. No commits were dropped or rewritten: #3040 now contains this exact linear commit as part of #3021–#3040. Closing only the redundant draft PR.