Add WebSocket upgrade dispatch to Node launcher

[timneutkens]

Summary

• read raw WebSocket upgrade primitives from @vercel/request-context after resolving the route module
• dispatch App Routes through upgradeHandler while preserving the existing HTTP fallback
• mirror normalized dynamic request URLs onto distinct raw upgrade requests
• keep incoming platform headers separate from Next.js response headers
• add focused Vitest coverage for fallback, upgrade dispatch, metadata forwarding, primitive identity, and error propagation

Testing

• pnpm --filter @next-community/adapter-vercel test
• pnpm --filter=next build in the Next.js WebSocket branch
• NEXT_TEST_PREFER_OFFLINE=1 pnpm test-start-webpack test/e2e/app-dir/websocket-route-handlers/websocket-route-handlers.test.ts (16 tests passed)

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[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
adapter-vercel-adapter	Ready	Preview, Comment	Jul 16, 2026 1:01pm

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	npm/​vitest@​0.34.6

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[socket-security]

Warning

Review the following alerts detected in dependencies.

According to your organization's Security Policy, it is recommended to resolve "Warn" alerts. Learn more about Socket for GitHub.

Action	Severity	Alert  (click "▶" to expand/collapse)
Warn		Critical CVE: When Vitest UI server is listening, arbitrary file can be read and executed CVE: GHSA-5xrq-8626-4rwp When Vitest UI server is listening, arbitrary file can be read and executed (CRITICAL) Affected versions: >= 4.0.0 < 4.1.0; < 3.2.6 Patched version: 3.2.6 From: packages/adapter/package.json → npm/vitest@0.34.6 ℹ Read more on: This package | This alert | What is a critical CVE? Next steps: Take a moment to review the security alert above. Review the linked package source code to understand the potential risk. Ensure the package is not malicious before proceeding. If you're unsure how to proceed, reach out to your security team or ask the Socket team for help at support@socket.dev. Suggestion: Remove or replace dependencies that include known critical CVEs. Consumers can use dependency overrides or npm audit fix --force to remove vulnerable dependencies. Mark the package as acceptable risk. To ignore this alert only in this pull request, reply with the comment @SocketSecurity ignore npm/vitest@0.34.6. You can also ignore all packages with @SocketSecurity ignore-all. To ignore an alert for all future pull requests, use Socket's Dashboard to change the triage state of this alert.
Warn		High CVE: npm vite: `server.fs.deny` bypass on Windows alternate paths CVE: GHSA-fx2h-pf6j-xcff vite: server.fs.deny bypass on Windows alternate paths (HIGH) Affected versions: >= 8.0.0 < 8.0.16; >= 7.0.0 < 7.3.5; < 6.4.3 Patched version: 6.4.3 From: pnpm-lock.yaml → npm/vitest@0.34.6 → npm/vite@5.4.21 ℹ Read more on: This package | This alert | What is a CVE? Next steps: Take a moment to review the security alert above. Review the linked package source code to understand the potential risk. Ensure the package is not malicious before proceeding. If you're unsure how to proceed, reach out to your security team or ask the Socket team for help at support@socket.dev. Suggestion: Remove or replace dependencies that include known high severity CVEs. Consumers can use dependency overrides or npm audit fix --force to remove vulnerable dependencies. Mark the package as acceptable risk. To ignore this alert only in this pull request, reply with the comment @SocketSecurity ignore npm/vite@5.4.21. You can also ignore all packages with @SocketSecurity ignore-all. To ignore an alert for all future pull requests, use Socket's Dashboard to change the triage state of this alert.

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