Data ownership, simplified

Who writes each field is now decided in one place only: the rules of each connection. For every group of fields, and down to a single field or language, you choose Source updates — the source always keeps it current — Empty fields only — the source fills a field only while it's empty in Nucleo — or Nucleo owns it, and the source never writes it.

With the rules doing the work, there's no longer a separate list of differences to review: what your rules allow is applied, and what they don't is left alone. Every change still shows up in the product's history, with restore.