-- Reverting this migration is a no-op: the labels we wrote in `up.sql`
-- are correct under any state of the schema (every dated row was indeed
-- exif-sourced before the resolver landed), and there's no signal that
-- distinguishes "labelled by this migration" from "labelled by the
-- ingest path post-resolver". Clearing them would break the drain's
-- eligibility filter again.
--
-- The companion migration `2026-05-06-000000_add_date_taken_source` is
-- the one to revert if you need to remove the column entirely.