Implement backward-compat bridge and resolution logic

[chargome]

The bridge translates sendDefaultPii into a resolved DataCollection object. Must intercept raw user options before any default-merging to distinguish undefined from false.

[linear-code]

JS-2497

[github-actions]

A PR closing this issue has just been released 🚀

This issue was referenced by PR #20967, which was included in the 10.54.0 release.