Streamed `http.client` spans have different `url.full` and `http.url` attribute values

[Lms24]

These attributes should have the same values (with http.url being deprecated), but it seems like they carry different URLs (host page vs. fetch request URLs?)

Example event: https://sentry.sentry.io/explore/traces/trace/079b7f956bdf49ab90f22219e3bda5d3/?node=span-b24f99cb80594e7d&project=4505160012660736&query=span.description%3A%22POST%20https%3A%2F%2Fgibpotato.app%2Fcollection%22&source=traces&statsPeriod=14d&targetId=b24f99cb80594e7d&timestamp=1781019734

[linear-code]

JS-2808

[suzunn]

I would start by tracing where the streamed span gets its legacy http.url value versus the newer url.full value, then force both attributes to be derived from the same normalized request URL at span creation time. The regression test should cover a streamed response where the page URL and fetch URL differ, because that is the shape that would catch an accidental fallback to the current browser location or request context. Keeping the deprecated http.url as a compatibility alias is fine, but it should be written from the same source as url.full until it is fully removed.

[github-actions]

A PR closing this issue has just been released 🚀

This issue was referenced by PR #21660, which was included in the 10.60.0 release.