fix(mobile): incorrect height of keyboard toolbar in ios (#8653)

### What Changes:
- Fix keyboard height calculation with the `KeyboardToolBarConfig.useScreenHeight = true`. More detials in: https://github.com/toeverything/blocksuite/pull/8645
- Add safe bottom padding for shrinked keyboard toolbar
- Add `VirtualKeyboard` polyfill. Close [AF-1573](https://linear.app/affine-design/issue/AF-1573/virtualkeyboard-polyfill-with-capacitor)
  - Since the `@capacitor/keyboard` dose not implement the `Keyboard.show()` method, this polyfill is not enabled now.

packages/frontend/apps/ios/capacitor.config.ts

@@ -1,4 +1,5 @@
 import type { CapacitorConfig } from '@capacitor/cli';
+import { KeyboardResize } from '@capacitor/keyboard';
 
 const config: CapacitorConfig = {
   appId: 'app.affine.pro',
@@ -17,6 +18,9 @@ const config: CapacitorConfig = {
     CapacitorHttp: {
       enabled: true,
     },
+    Keyboard: {
+      resize: KeyboardResize.Native,
+    },
   },
 };