feat: implement creator_id factor

plugin/filter/filter.go

@@ -9,6 +9,7 @@ import (
 // MemoFilterCELAttributes are the CEL attributes for memo.
 var MemoFilterCELAttributes = []cel.EnvOption{
 	cel.Variable("content", cel.StringType),
+	cel.Variable("creator_id", cel.IntType),
 	// As the built-in timestamp type is deprecated, we use string type for now.
 	// e.g., "2021-01-01T00:00:00Z"
 	cel.Variable("create_time", cel.StringType),