Terminal search/find leaves highlights behind

Does this issue occur when all extensions are disabled?: Yes

- VS Code Version: 1.132.1 (Universal)
- OS Version: Darwin arm64 25.5.0

Steps to Reproduce:

1. Populate an integrated terminal with some text
2. Open the "Find" panel
3. Search for some string so that there are multiple matches
4. Close the "Find" panel
5. Repeat steps 3-4 with multiple strings
6. Notice leftover highlighted bits

This started happening a few releases ago. I'm not sure which one exactly, but maybe within the past 3-6 months?

The issue is bound to each individual terminal, so killing a terminal or opening a new terminal will mitigate the issue. The video shows the behavior in more detail.

## Video Reproduction

https://github.com/user-attachments/assets/fd335a24-785e-43f6-a781-4d76f94c4395