fix: highlight tab focused buttons and Dir List (#10153)

Co-authored-by: 0.618 <o.6180339@gmail.com>

packages/application/style/buttons.css

@@ -16,6 +16,10 @@ button {
   border-radius: var(--jp-border-radius);
 }
 
+button:focus-visible {
+  border: 1px solid var(--jp-brand-color1);
+}
+
 button.jp-mod-styled.jp-mod-accept {
   background: var(--md-blue-500);
   border: 0;

packages/filebrowser/style/base.css

@@ -89,6 +89,12 @@
   background: var(--jp-brand-color1);
 }
 
+.jp-FileBrowser-toolbar.jp-Toolbar
+  .jp-Toolbar-item:first-child
+  .jp-ToolbarButtonComponent:focus-visible {
+  background-color: var(--jp-brand-color0);
+}
+
 .jp-FileBrowser-toolbar.jp-Toolbar
   .jp-Toolbar-item:first-child
   .jp-ToolbarButtonComponent
@@ -129,6 +135,10 @@
   outline: 0;
 }
 
+.jp-DirListing:focus-visible {
+  border: 1px solid var(--jp-brand-color1);
+}
+
 .jp-DirListing-header {
   flex: 0 0 auto;
   display: flex;