[`CListViewBaseItemChrome`] crashes on `SetSelectionIndicatorBackground`

### Describe the bug

See the video

https://github.com/user-attachments/assets/85149a90-448f-48a4-9228-53008d3dfe57

### Why is this important?

Does not allow to use the derived control,
Also affects Syncfusion controls

### Steps to reproduce the bug

1. Unzip the repro app [Ecierge.Uno.Controls.zip](https://github.com/user-attachments/files/22136317/Ecierge.Uno.Controls.zip)
2. Select `Ecierge.Uno.App (WinAppSDK Packaged native dbg)` profile and run the app
3. Open my custom ComboBox and select item
4. Open it again and try selecting another item
5. Click elsewhere
6. Open the ComboBox again
7. See crash

### Actual behavior

App crashes

### Expected behavior

Item is selected

### Screenshots

_No response_

### NuGet package version

WinUI 3 - Windows App SDK 1.7.3: 1.7.250606001

### Windows version

Windows 11 (24H2): Build 26100

### Additional context

_No response_

Start by unpacking the linked Ecierge.Uno.Controls.zip repro and running the WinAppSDK Packaged native debug profile on Windows 11 with Windows App SDK 1.7.3. Reproduce the crash around CListViewBaseItemChrome and SetSelectionIndicatorBackground while tracing the failing path. Done means reopening the ComboBox and selecting another item no longer crashes.

Written by the indexing model from the issue text.