The application must have a host view since the keyboard client must be part of the responder chain to function. The host view controller is (null)

### 请描述遇到的问题，以及您所期望的正确的结果

iOS混编模式下会偶现The host view controller is (null)

### 请说明如何操作会遇到上述问题

正常打开页面、关闭页面操作

### 在下面填入关键复现代码

[✓] Flutter (Channel stable, 3.0.5, on macOS 13.6 22G120 darwin-arm, locale
zh-Hans-CN)
Checking Android licenses is taking an unexpectedly long time...[✓] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
[✓] Xcode - develop for iOS and macOS (Xcode 15.0.1)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2020.3)
[✓] VS Code (version 1.66.2)
[✓] Connected device (3 available)
[✓] HTTP Host Availability

• No issues found!

### 复现的平台

iOS

### Flutter SDK版本

3.0.5

### FlutterBoost版本

4.2.0

### 是否延迟初始化FlutterBoost

No

### 解决方案

The payload names no files or tests. Start by reproducing the normal iOS page open and close flow in the reported Flutter 3.0.5 and FlutterBoost 4.2.0 hybrid setup, then trace when the host view controller becomes null. Done means identifying and preventing the intermittent error, with a regression check for that flow.

Written by the indexing model from the issue text.