[chore] [receiver/datadogreceiver] Migrate ReverseProxy.Director to Rewrite

[singhvibhanshu]

Description

This PR migrates the intake reverse proxy from httputil.ReverseProxy.Director to Rewrite. Director is deprecated as of Go 1.26 in favor of Rewrite, which has been available since Go 1.20. The rewrite hook operates on ProxyRequest.Out rather than the request directly.

Unlike Director, Rewrite strips the X-Forwarded-* headers before it is called and does not re-add them. This PR calls pr.SetXForwarded() to preserve the previous X-Forwarded-For behavior, keeping the outbound request identical.

Link to tracking issue

Fixes #50418

Testing

Tuned.

Documentation

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Authorship

• I, a human, wrote this pull request description myself.

[opentelemetry-pr-dashboard]

Pull request dashboard status

Waiting on the author · refreshed 2026-08-22 17:21 UTC

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[paulojmdias]

PTAL into CI errors