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Write the submitted fields, with provenance for what changed.

Only a transition of the marketing flag writes anything beyond the row: re-sending the state a page is already showing must not append a second grant, or the evidence table fills with events nobody caused. The consent row is appended, never updated — a grant that rewrote the previous revoke in place would destroy the only proof of what happened between them.

esp_state is marked pending on a transition only when a sync is actually owed against a contact that exists: this deployment knows an esp_contact_id for the person. With no contact the audience entry does not exist yet, and a pending would be a drain forever chasing nothing — or, once a re-grant restores a contact id, one deleting the audience member of somebody who just opted in.

No provider call happens here, for the rule the deletion route states at length: a network hop under a row lock is how one slow vendor becomes a stalled database.