Use composite evidence keys in rollback dependencies

scripts/proposal_apply_lifecycle.py

@@ -489,7 +489,7 @@ begin
   end if;
   select count(*) into downstream_dependency_count
     from (
-      select ce.id
+      select ce.claim_id
         from public.claim_evidence ce
        where (ce.claim_id = any({claim_ids}) or ce.source_id = any({source_ids}))
          and not ({owned_evidence_predicate})

tests/test_proposal_apply_lifecycle.py

@@ -499,6 +499,8 @@ def test_compensating_rollback_is_atomic_deterministic_and_refuses_state_drift()
     assert delete_positions == sorted(delete_positions)
     assert "set status = 'canceled'" in rollback_sql
     assert "downstream_dependency_count" in rollback_sql
+    assert "select ce.claim_id" in rollback_sql
+    assert "select ce.id" not in rollback_sql
     assert "downstream dependenc(ies) exist" in rollback_sql
     assert "immutable approval snapshot drifted" in rollback_sql