adicionando instrumentos no editor de patterns

assets/js/creations/state.js

@@ -12,7 +12,7 @@ import { DEFAULT_VOLUME, DEFAULT_PAN } from "./config.js";
 const patternState = {
   tracks: [],
   activeTrackId: null,
-  activePatternIndex: 0,
+  activePatternIndex: null,
 };
 
 const globalState = {
@@ -164,7 +164,7 @@ export function resetProjectState() {
   Object.assign(appState.pattern, {
     tracks: [],
     activeTrackId: null,
-    activePatternIndex: 0,
+    activePatternIndex: null,
     focusedBasslineId: null,
   });