fix(editor): editor behavior and styles (#14498)

fix #14269 
fix #13920
fix #13977
fix #13953
fix #13895
fix #13905
fix #14136
fix #14357
fix #14491

#### PR Dependency Tree


* **PR #14498** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Bug Fixes**
  * Callout and toolbar defaults now reliably show grey backgrounds
  * Keyboard shortcuts behave better across layouts and non-ASCII input
  * Deleted workspaces no longer appear in local listings

* **New Features**
  * Cell editing now respects pre-entry validation hooks
* Scrollbars use themeable variables and include Chromium compatibility
fixes

* **Style**
  * Minor UI color adjustment for hidden properties

* **Tests**
  * Added unit tests for table column handling and keymap behavior
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/affine/shared/src/styles/scrollbar-style.ts

@@ -1,5 +1,7 @@
 import { css, unsafeCSS } from 'lit';
 
+import { unsafeCSSVarV2 } from '../theme/css-variables';
+
 /**
  * You should add a container before the scrollbar style to prevent the style pollution of the whole doc.
  */
@@ -28,7 +30,7 @@ export const scrollbarStyle = (container: string) => {
     }
     ${unsafeCSS(container)}::-webkit-scrollbar-thumb {
       border-radius: 2px;
-      background-color: #b1b1b1;
+      background-color: ${unsafeCSSVarV2('icon/secondary', '#b1b1b1')};
     }
     ${unsafeCSS(container)}::-webkit-scrollbar-corner {
       display: none;