preventFocus() TypeError when the window is the target focus or blur

### Provide a general summary of the issue here

`preventFocus()` throws a `TypeError` when the window itself is the target of a `focus` or `blur` event while its listeners are attached. Regression in `react-aria@3.52.0`; `3.51.0` is unaffected and `3.52.1` still throws. So far as I can tell this is log spam rather than user impacting.

### 🤔 Expected Behavior?

Window-targeted `focus` and `blur` events are ignored by this code, as they were before 3.52.0.

### 😯 Current Behavior

An uncaught `TypeError`, which we see via Sentry:

```txt
Chrome: TypeError: Failed to execute 'contains' on 'Node': parameter 1 is not of type 'Node'.
WebKit: TypeError: Argument 1 ('other') to Node.contains must be an instance of Node
```

#9632 (`c1a6152e`) reworked `preventFocus()` for shadow DOM. It attaches capturing `focus`/`blur` listeners to `getOwnerWindow(target)`, and the handlers moved from reference equality to `nodeContains()` which doesn't cope with window targets.

### 💁 Possible Solution

Guard `nodeContains` calls with an `isNode` check.

### 🔦 Context

As noted above we don't see serious impact from this, just Sentry logs, but it seems like a logical error worth fixing.

### 🖥️ Steps to Reproduce

I see this in Sentry but I've found it hard to get a real-world manual reproduction, presumably it's a RAF timing quirk. This proposed test triggers the error scenarios:

https://github.com/adobe/react-spectrum/compare/main...microbit-matt-hillsdon:react-spectrum:preventfocus-window-target-repro

### Version

3.52.1

### What browsers are you seeing the problem on?

Chrome

### If other, please specify.

_No response_

### What operating system are you using?

Mac, Windows

### 🧢 Your Company/Team

_No response_

### 🕷 Tracking Issue

_No response_

Start by locating preventFocus() and nodeContains() in the react-spectrum source, then review the shadow DOM changes from #9632 and the linked reproduction. Verify that window-targeted focus and blur events no longer throw while existing node-target behavior remains unchanged, using the proposed reproduction as the regression check.

Written by the indexing model from the issue text.