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)

packages/frontend/apps/android/src/app.tsx

@@ -120,7 +120,9 @@ framework.impl(VirtualKeyboardProvider, {
           const navBarHeight = (await AffineTheme.getSystemNavBarHeight())
             .height;
           callback({
-            visible: true,
+            // When an physical keyboard is connected, the virtual keyboard height is 0,
+            // even though the `keyboardWillShow` event is still triggered.
+            visible: info.keyboardHeight !== 0,
             height: info.keyboardHeight - navBarHeight,
           });
         })().catch(console.error);