refactor(editor): always show keyboard toolbar in mobile (#13384)

Close
[AF-2756](https://linear.app/affine-design/issue/AF-2756/激活输入区的时候，展示toolbar，适配不弹虚拟键盘的场景，比如实体键盘)

#### PR Dependency Tree


* **PR #13384** 👈

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

* **New Features**
* Improved virtual keyboard handling by introducing static keyboard
height and app tab safe area tracking for more consistent toolbar
behavior.

* **Bug Fixes**
* Enhanced keyboard visibility detection on Android and iOS, especially
when a physical keyboard is connected.

* **Refactor**
* Simplified and streamlined keyboard toolbar logic, including delayed
panel closing and refined height calculations.
* Removed unused or redundant toolbar closing methods and position
management logic.

* **Style**
* Updated toolbar and panel styles for better positioning and layout
consistency.
  * Adjusted and removed certain mobile-specific padding styles.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->


#### PR Dependency Tree


* **PR #13384** 👈

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

blocksuite/affine/widgets/keyboard-toolbar/src/styles.ts

@@ -7,6 +7,7 @@ export const keyboardToolbarStyles = css`
     position: fixed;
     display: block;
     width: 100vw;
+    bottom: 0;
   }
 
   .keyboard-toolbar {
@@ -60,14 +61,18 @@ export const keyboardToolbarStyles = css`
 
 export const keyboardToolPanelStyles = css`
   affine-keyboard-tool-panel {
+    display: block;
+    overflow-y: auto;
+    box-sizing: border-box;
+    background-color: ${unsafeCSSVarV2('layer/background/primary')};
+  }
+
+  .affine-keyboard-tool-panel-container {
     display: flex;
     flex-direction: column;
     gap: 24px;
     width: 100%;
     padding: 16px 4px 8px 8px;
-    overflow-y: auto;
-    box-sizing: border-box;
-    background-color: ${unsafeCSSVarV2('layer/background/primary')};
   }
 
   ${scrollbarStyle('affine-keyboard-tool-panel')}