revise the way editor toolbar sticks to the bottom

lib/widgets/editor/editor_toolbar.dart

@@ -71,6 +71,7 @@ class EditorToolbar extends HookWidget {
             child: visible
                 ? Material(
                     color: Theme.of(context).canvasColor,
+                    child: SafeArea(
                       child: SizedBox(
                         height: _height,
                         width: double.infinity,
@@ -82,6 +83,7 @@ class EditorToolbar extends HookWidget {
                           ),
                         ),
                       ),
+                    ),
                   )
                 : const SizedBox.shrink(),
           ),
@@ -98,13 +100,11 @@ class BottomSticky extends StatelessWidget {
   const BottomSticky({required this.child});
 
   @override
-  Widget build(BuildContext context) => SafeArea(
-        child: Column(
-          mainAxisAlignment: MainAxisAlignment.spaceBetween,
-          children: [
-            const Spacer(),
-            child,
-          ],
+  Widget build(BuildContext context) => Positioned(
+        bottom: 0,
+        child: SizedBox(
+          width: MediaQuery.of(context).size.width,
+          child: child,
         ),
       );
 }