## Summary
Fixes `METADATA_VALIDATION_FAILED` / “view field already exists” when
saving dashboard **record table** widgets after the first persist (e.g.
several table widgets on one dashboard).
## Problem
Draft view columns used **client-generated** `viewField` ids. After
save, the API stored **different** ids. The next upsert still sent the
old draft ids as `viewFieldId`. The server only matched on that id,
missed every row, and tried to **create** columns that already existed
for the same `fieldMetadataId` + view.
