fix: 修复 SQL*Plus 脚本编码问题，确保正确处理输入脚本

src/sources/view/oracle-sqlplus.js

@@ -143,7 +143,7 @@ function runSqlplus({ sqlplusPath, script, timeoutMs, encoding }) {
       }
       resolve(output);
     });
-    child.stdin.end(script, "utf8");
+    child.stdin.end(iconv.encode(script, encoding || "gbk"));
   });
 }