[v11] httpclient: Use granular dataCollection settings instead of sendDefaultPii gate

[chargome]

In the sendDefaultPii→ dataCollection migration (#20929), we added a backwards-compat guard in packages/browser/src/integrations/httpclient.ts that preserves the old all-or-nothing behavior when dataCollectionis not explicitly set by the user.

[linear-code]

JS-2580