Add policy-controlled URL query data to Ktor client spans

## Problem

Ktor (`SentryKtorClientPlugin`) does not apply URL details to the span and thus lacks data fields / attributes like query.

In the next major we should add `urlDetails.applyToSpan(span)`.

We didn't do this as part of #5983 due to risk of leaking data to Sentry when doing this in a minor.

Start at SentryKtorClientPlugin and trace where urlDetails is available for client spans. Confirm the next-major behavior applies policy-controlled URL query data without changing the minor-release behavior; done when the relevant span attributes reflect the intended URL details.

Written by the indexing model from the issue text.