Add HTTP server request headers from OpenTelemetry span attributes to sentry request in payload

[adinauer]

📜 Description

Add HTTP headers in OpenTelemetry span attributes to request.headers.

To actually make this work, customers need to explicitly name the headers they want to see in Sentry in the OpenTelemetry config https://opentelemetry.io/docs/zero-code/java/agent/instrumentation/http/#capturing-http-request-and-response-headers

💡 Motivation and Context

Enable reporting of request headers.

💚 How did you test it?

📝 Checklist

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[github-actions]

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against 1d89f04

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	395.13 ms	479.50 ms	84.37 ms
Size	1.65 MiB	2.31 MiB	678.16 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
00c8eeb	415.32 ms	428.08 ms	12.76 ms

App size

Revision	Plain	With Sentry	Diff
00c8eeb	1.70 MiB	2.36 MiB	671.98 KiB

Previous results on branch: feat/otel-server-request-headers

Startup times

Revision	Plain	With Sentry	Diff
01d4a6e	408.89 ms	451.35 ms	42.45 ms
461c657	405.82 ms	430.92 ms	25.10 ms

App size

Revision	Plain	With Sentry	Diff
01d4a6e	1.65 MiB	2.31 MiB	677.61 KiB
461c657	1.65 MiB	2.31 MiB	677.61 KiB