`ConnectedAnimation` causes memory leak

### Describe the bug

Trigger `ConnectedAnimation` repeatedly, memory usage will increase steadily.

### Why is this important?

Frequent operations can cause a crash.

### Steps to reproduce the bug

There are two ways to reproduce this:
The first one:
1. Debug attached solution: [ConnectedAnimationMemoryLeak.zip](https://github.com/user-attachments/files/30036901/ConnectedAnimationMemoryLeak.zip)
2. Click repeatedly rectangle with text leak.
3. Observe Process Memory in Diagnostic Tools

The second one:
1. Open WinUI 3 Gallery
2. Open Task Manager, search WinUI 3 Gallery
3. Go to Motion > Connected Animation
4. Locate to first sample, click Item 1 and Go Back repeatedly.
5. Check memory usage in Task Manager.

### Actual behavior

Process memory usage increase steadily.

### Expected behavior

No memory leak.

### Screenshots

### NuGet package version

2.2.1

### Windows version

Windows 11 (26H1): Build 28000

### Additional context

_No response_

Start with the attached ConnectedAnimationMemoryLeak.zip and reproduce the leak by repeatedly clicking the rectangle. Compare this with the WinUI 3 Gallery Motion > Connected Animation sample while monitoring memory in Diagnostic Tools or Task Manager. Done means repeated navigation no longer causes process memory to increase steadily.

Written by the indexing model from the issue text.