Move move_money into a wasm module, add dynamic node test that uses move_money

wit/dynamic_node.wit

@@ -23,10 +23,12 @@ interface types {
 
     resource csv-readers {
         get-reader: func(name: string) -> option<csv-reader>;
+        read-into-string: func(name: string) -> string;
     }
 
     resource csv-writer {
         write-row: func(row: list<tuple<string, string>>);
+        write-string: func(row: string);
     }
 
     resource read-map {