Additional line breaks added after submitting prompt with Pick and Polish attachment

### Short summary

Additional line breaks added after submitting prompt with Pick and Polish attachment

### Affected version or release

0.2.24

### Installation context

_No response_

### What happened?

https://github.com/user-attachments/assets/82accf67-90e8-497f-9e70-0fa857693e9c

### Steps to reproduce

1. use pick and polish to attach an element
2. Type a prompt with no line breaks and hit enter

Expected - Prompt shows as entered upon submit
Actual - 4 line breaks are added above prompt

### Expected behavior

_No response_

### Additional context

_No response_

No source file or test is named. First reproduce the issue in GitHub Copilot app 0.2.24 using Pick and Polish, then trace the prompt submission and rendering path; it is done when a prompt without line breaks remains unchanged after submission.

Written by the indexing model from the issue text.