Introduce Shapelock (#480)

* Introduce shape lock

* Format code with prettier

* Do not reset elementLocked on selection change

* Don't set isSelected to true if element is locked

* Don't reset the cursor

* Move reset cursor call to better spot

* Run prettier + lint

src/appState.ts

@@ -9,6 +9,7 @@ export function getDefaultAppState(): AppState {
     resizingElement: null,
     editingElement: null,
     elementType: "selection",
+    elementLocked: false,
     exportBackground: true,
     currentItemStrokeColor: "#000000",
     currentItemBackgroundColor: "transparent",