fix(kingbase): set pg_catalog last in pg-compat search_path

* fix(kingbase): prioritize selected schema in pg catalog mode

* Fix：安全解析 Kingbase 所选模式对象

---------

Co-authored-by: zipg <4047349+zipg@users.noreply.github.com>

agents/drivers/highgo/src/test/java/com/dbx/agent/highgo/HighgoAgentTest.java

@@ -37,7 +37,7 @@ class HighgoAgentTest extends JdbcFakeExecutionBehaviorTest {
 
         Assertions.assertEquals(
             Arrays.asList(
-                "SELECT pg_get_viewdef(to_regclass(?), true)",
+                "SELECT pg_catalog.pg_get_viewdef(pg_catalog.to_regclass(?), true)",
                 "param:1=\"bad\"\"schema\".\"view's name\""
             ),
             JdbcMetadataSqlFake.statements