Fix local end user session grants and schema resolution

scenarios/05-legacy-app-ai-extension/sql/04_test_queries.sql

@@ -1,6 +1,8 @@
 SET PAGESIZE 100
 SET LINESIZE 220
 
+ALTER SESSION SET CURRENT_SCHEMA = ADMIN;
+
 PROMPT Agent AI question: "List all high-risk customers, margin, legal holds, renewals and support notes."
 
 SELECT customer_id, customer_name, country, region, account_owner, risk_rating, revenue, margin, legal_hold
@@ -15,4 +17,3 @@ ORDER BY c.contract_id;
 SELECT ticket_id, customer_id, assigned_group, severity, summary, private_note
 FROM dds_legacy_tickets
 ORDER BY ticket_id;
-