Revert "fix!: revert UI behavior of `fetch_if_empty`"

This reverts commit 1b9cd8b8.

Reverting the current behavior as proposed in https://github.com/frappe/frappe/pull/22916 creates a behavior inconsistency in Dokos. In my opinion, the UI behavior should be similar to the back-end behavior.

Therefore I propose to revert the previous reversion to keep the behavior present in v3

See !790 (merged) See !194 (merged)