Introduce NsdManager API for in-place service updates without re-announcement.

This commit builds upon CL aosp/2817455 by adding a new NsdManager API to
update registered services directly, eliminating the need for exit and
re-announcement messages. This preserves compatibility with existing
apps without requiring an API bump. If an app registers a service with
the same listener and NsdServiceInfo, it's treated as an update request.

Bug: 309372239
Test: TH
Change-Id: Ib84ddf0d92e757eaef225f3e32f5223bc50c8fd6