fix backend tests

migration.sql

@@ -222,15 +222,19 @@ CREATE TABLE IF NOT EXISTS "distance" (
 );
 
 
-CREATE UNIQUE INDEX one_role_per_group_per_user ON user_role
-WHERE EXISTS (
+CREATE TRIGGER prevent_multiple_roles_same_cluster
+BEFORE INSERT ON user_role
+BEGIN
+    SELECT CASE 
+        WHEN EXISTS (
             SELECT 1
-    FROM role r1
-    JOIN role r2 ON r1.id = user_role.role_id
-    WHERE r1."group" = r2."group"
-    AND r2.id IN (
-        SELECT role_id 
-        FROM user_role ur2 
-        WHERE ur2.user_id = user_role.user_id
+            FROM user_role ur
+            JOIN role r1 ON ur.role_id = r1.id
+            JOIN role r2 ON r1."cluster" = r2."cluster"
+            WHERE ur.user_id = NEW.user_id
+            AND r2.id = NEW.role_id
+            AND r1.id != NEW.role_id
         )
-);
+        THEN RAISE(ABORT, 'User already has a role in this cluster')
+    END;
+END;