ItemsRepeater element recycling has bug for ItemsSource index 0

Nobody has claimed this yet.

### Describe the bug

Using `ItemsRepeater` with `LinedFlowLayout` and checking recycling behaviour by `ElementPrepared` and `ElementClearing` event.
Two deferent element bound for index 0 of ItemsSource.

log
```
ElementPrepared Index:0 Ptr:3211120194192
ElementPrepared Index:0 Ptr:3211120194544
ElementPrepared Index:1 Ptr:3211120197360
ElementPrepared Index:2 Ptr:3211120199472
ElementPrepared Index:3 Ptr:3211120195952
ElementPrepared Index:4 Ptr:3211120195248
ElementPrepared Index:5 Ptr:3211120192432
ElementPrepared Index:6 Ptr:3211120196304
ElementPrepared Index:7 Ptr:3211120197008
ElementPrepared Index:8 Ptr:3211120197712
ElementPrepared Index:9 Ptr:3211120193136
```

```xaml

```

```cs
private void itemsRepeater_ElementPrepared(ItemsRepeater sender, ItemsRepeaterElementPreparedEventArgs args)
{
nint ptr = ((IWinRTObject)args.Element).NativeObject.ThisPtr;
Debug.WriteLine($"ElementPrepared Index:{args.Index} Ptr:{ptr.ToInt64()}");
}

private void itemsRepeater_ElementClearing(ItemsRepeater sender, ItemsRepeaterElementClearingEventArgs args)
{
nint ptr = ((IWinRTObject)args.Element).NativeObject.ThisPtr;
Debug.WriteLine($"ElementClearing Ptr:{ptr.ToInt64()}");
}
```

Next, scrolling down, down, down.., Two elements for Index 0 repeats Prepared and Clearing.

```
ElementPrepared Index:0 Ptr:3211131401264
ElementPrepared Index:0 Ptr:3211131409360
ElementClearing Ptr:3211131401264
ElementPrepared Index:0 Ptr:3211131401264
ElementClearing Ptr:3211131409360
ElementPrepared Index:0 Ptr:3211131409360
ElementClearing Ptr:3211131401264
ElementPrepared Index:0 Ptr:3211131401264
ElementClearing Ptr:3211131409360
ElementPrepared Index:0 Ptr:3211131409360
ElementClearing Ptr:3211131401264
ElementPrepared Index:0 Ptr:3211131401264
ElementClearing Ptr:3211131409360
ElementPrepared Index:0 Ptr:3211131409360
ElementClearing Ptr:3211131401264
ElementPrepared Index:0 Ptr:3211131401264
ElementClearing Ptr:3211131409360
ElementPrepared Index:0 Ptr:3211131409360
ElementClearing Ptr:3211131401264
ElementPrepared Index:0 Ptr:3211131401264
```

### Why is this important?

For apps like microsoft photo, ItemsRepeater's `ElementPrepared` and `ElementClearing` event timing is very important for managing thumbnail image.

### Steps to reproduce the bug

### Repro
[ItemsRepeaterBug01Repro.zip](https://github.com/user-attachments/files/23907846/ItemsRepeaterBug01Repro.zip)

1. Start Debug and Scroll down, down, down.
2. See Visual Studio Debug Output.

### Actual behavior

- Two Element bound for Index 0.
- Two elements for Index 0 repeats Prepared and Clearing.

### Expected behavior

Element for Index 0 behaves like for Index 1. Bound Single Item and dont repeat Prepared and Clearing.

### Screenshots

_No response_

### NuGet package version

WinUI 3 - Windows App SDK 1.8.3: 1.8.251106002

### Windows version

Windows 11 (24H2): Build 26100

### Additional context

_No response_

Start with the attached ItemsRepeaterBug01Repro.zip and reproduce the issue using ItemsRepeater with LinedFlowLayout while watching the ElementPrepared and ElementClearing output. Trace the recycling path for ItemsSource index 0 and compare it with index 1. Done means index 0 has one element and does not repeatedly prepare and clear during scrolling.

Written by the indexing model from the issue text.