More macOS 13 compatibility issues

### Problem

On macOS 13, the editor crashes on launch, then shows a blank view after workaround.

**Crash trace:**
```
-[NSNib _initWithNibNamed:bundle:options:]
-[NSViewController _nibWithName:bundle:]
-[NSViewController loadView]
```

### Workaround

The following changes make it work on macOS 13, but we don't fully understand why they're only needed on macOS 13:

1. Replace `super.loadView()` with `self.view = NSView()` in `TextViewController`, `FindViewController`, `SuggestionViewController`

2. Move `styleTextView/ScrollView/MinimapView()` before `FindViewController` creation in `TextViewController.loadView()`

See: https://github.com/nekohasekai/CodeEditSourceEditor/commit/941f378