[BUG] Instrumentation does not work

[ilovemesomeramen]

Describe the bug

When i add a instrumentation.ts file with a basic OTEL config no traces are being collected and sent when i build with opennext.

Not sure if this is supposed to work but since i found this Issue: #171 which is Closed i assume it should work.

Steps to reproduce

Min reproducible example: https://github.com/ilovemesomeramen/opennextjs-cloudflare-instrumentation

1. Clone the repo
2. docker compose up in the debug folder
   • This starts a small web server which logs the received requests
3. npm run build && npm run start
4. visit http://localhost:3000
5. After a view seconds observe the trace POST to the docker compose server
6. Stop the next server and run npm run preview
7. visit http://localhost:8787
8. no traces are sent

Expected behavior

Traces should be sent and collected

@opennextjs/cloudflare version

1.6.3

Wrangler version

4.27.0

next info output

Operating System:
  Platform: linux
  Arch: x64
  Version: #1 SMP PREEMPT_DYNAMIC Thu, 17 Jul 2025 20:47:04 +0000
  Available memory (MB): 62086
  Available CPU cores: 16
Binaries:
  Node: 22.14.0
  npm: 11.4.2
  Yarn: N/A
  pnpm: 10.13.1
Relevant Packages:
  next: 15.3.5 // There is a newer version (15.4.5) available, upgrade recommended! 
  eslint-config-next: 15.3.5
  react: 19.1.1
  react-dom: 19.1.1
  typescript: 5.8.3
Next.js Config:
  output: N/A
 ⚠ There is a newer version (15.4.5) available, upgrade recommended! 
   Please try the latest canary version (`npm install next@canary`) to confirm the issue still exists before creating a new issue.
   Read more - https://nextjs.org/docs/messages/opening-an-issue

Additional context

No response

[conico974]

The default OTEL Node sdk cannot work on cloudflare or any other serverless provider.
It expects a server to stay up at all time