perf: add GIN indexes on clazz JSONB columns and date-range indexes

- GIN indexes on students/teachers (jsonb_path_ops) for fast user lookups
- Composite index on clazz (is_repeat, start_from, end_by) for date range queries
- Indexes on clazz_repeat (clazz_id, repeat_start, repeat_end) for joins

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

htyts/tests/ts_e2e_http.rs

@@ -52,6 +52,7 @@ fn mint_sudo_jwt() -> String {
         tags: None,
         current_org_id: None,
         current_org_role_keys: None,
+            current_department_id: None,
     };
     jwt_encode_token(inner).expect("jwt_encode_token")
 }