uid2: apply refresh outcomes to the targeting cache

[mosherBT]

Why

A UID2 refresh outcome has to land in the targeting cache: a fresh token should replace the cached EID in place, and a dead one (opt-out, expired) should evict it. web-sdk has the protocol client (#328) but nothing that updates the cache.

What Changed

• addons: applyUid2Refresh(config, source, result) in lib/addons/uid2-refresh.ts — on success, rewrites the matching EID's uids to [{ atype: 3, id: advertising_token }] and its _ref from the response body; on optout, invalid_token or expired_token, removes the EID; any other error leaves the cache untouched for retry. Updates each stored cache copy independently and sends the optable-targeting:change event after each write.
• addons: RefreshableEID type (EID & { _ref?: Uid2RefData }).
• core: LocalStorage.updateTargeting(update) — applies an update to every stored copy of the targeting response independently, so the private raw copy and a wrapper's merged public copy never overwrite each other.

How to Test

Unit tests cover: success rewrite (uids + _ref, other EIDs untouched, event sent), independent private/public copy updates, definitive-rejection eviction, transient errors leaving the cache untouched, unknown source no-op, empty cache no-op.

• Tested
• Docs updated

Notes

• Breaking change
• Requires release