Function pest_ide::render_code

#[no_mangle]
pub extern "C" fn render_code(
    rule_name: JavaStr, 
    rule_name_len: i32, 
    user_code: JavaStr, 
    user_code_len: i32
) -> JavaStr

After loading the VM, this function can parse the code with the currently loaded VM. Assumes the VM is already loaded, otherwise it'll panic.