Remove unnecessary default attributes

js/entity/UnknownPinEntity.js

@@ -1,15 +1,22 @@
 import P from "parsernostrum"
 import Grammar from "../serialization/Grammar.js"
+import GuidEntity from "./GuidEntity.js"
 import PinEntity from "./PinEntity.js"
 
 export default class UnknownPinEntity extends PinEntity {
 
+    static attributes = {
+        ...super.attributes,
+        PinId: GuidEntity
+    }
+
     static grammar = this.createGrammar()
 
     /** @returns {P<UnknownPinEntity>} */
     static createGrammar() {
         return P.seq(
-            P.reg(new RegExp(`(${Grammar.Regex.Symbol.source})\\s*\\(\\s*`), 1),
+            // Lookbehind
+            P.reg(new RegExp(`(${Grammar.Regex.Symbol.source}\\s*)\\(\\s*`), 1),
             Grammar.createAttributeGrammar(this).sepBy(Grammar.commaSeparation),
             P.reg(/\s*(?:,\s*)?\)/)
         ).map(([lookbehind, attributes, _2]) => {