Merge pull request #497: idempotent 022 canonical facts

Retry-safe RLS policies (DROP POLICY IF EXISTS) + header fix.

sql/022_canonical_facts.sql

@@ -1,4 +1,4 @@
--- 020_canonical_facts.sql — 0pt canonical structured observations (X-800 / Scrape).
+-- 022_canonical_facts.sql — 0pt canonical structured observations (X-800 / Scrape).
 --
 -- 0pt owns normalized OBSERVED facts (what a source said, when, from which
 -- artifact). L0RE owns epistemic propositions/assertions and projections; it
@@ -82,18 +82,21 @@ CREATE INDEX IF NOT EXISTS idx_canonical_relations_object
 
 ALTER TABLE opt_canonical_entities ENABLE ROW LEVEL SECURITY;
 ALTER TABLE opt_canonical_entities FORCE ROW LEVEL SECURITY;
+DROP POLICY IF EXISTS opt_canonical_entities_tenant ON opt_canonical_entities;
 CREATE POLICY opt_canonical_entities_tenant ON opt_canonical_entities
   USING (tenant_id = current_setting('app.opt_canonical_tenant_id', true))
   WITH CHECK (tenant_id = current_setting('app.opt_canonical_tenant_id', true));
 
 ALTER TABLE opt_canonical_facts ENABLE ROW LEVEL SECURITY;
 ALTER TABLE opt_canonical_facts FORCE ROW LEVEL SECURITY;
+DROP POLICY IF EXISTS opt_canonical_facts_tenant ON opt_canonical_facts;
 CREATE POLICY opt_canonical_facts_tenant ON opt_canonical_facts
   USING (tenant_id = current_setting('app.opt_canonical_tenant_id', true))
   WITH CHECK (tenant_id = current_setting('app.opt_canonical_tenant_id', true));
 
 ALTER TABLE opt_canonical_relations ENABLE ROW LEVEL SECURITY;
 ALTER TABLE opt_canonical_relations FORCE ROW LEVEL SECURITY;
+DROP POLICY IF EXISTS opt_canonical_relations_tenant ON opt_canonical_relations;
 CREATE POLICY opt_canonical_relations_tenant ON opt_canonical_relations
   USING (tenant_id = current_setting('app.opt_canonical_tenant_id', true))
   WITH CHECK (tenant_id = current_setting('app.opt_canonical_tenant_id', true));