The MV SELECTed COALESCE(user_id, zero-uuid) but GROUPed BY raw user_id,
so a global enrichment claim (user_id NULL) and a default-user behavior
claim (user_id = zero-uuid) for the same edge produced two rows that
collide on idx_claim_fusion_pk, breaking REFRESH ... CONCURRENTLY.
Exposed by the #219 listener_behavior same_scene_as/alias_of writes.
New migration rebuilds the MV grouping by the COALESCE'd user_id so the
two fuse into one row.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
kami
d497588c87