Bug: Drive letter isn't removed when at start from renaming

### Description

Using WinAreo tweaker https://winaerotweaker.com/ I move the drive letter to the start, Files isn't detecting this and will double up the letter on renaming

### Steps To Reproduce

1. Download https://winaerotweaker.com
2. Enable `Winareo tweaker > File Explorer > Drive letters > Drive letters before label`
3. Restart Windows
4. Change Drive name in Files

### Files Version

4.2.34.0

### Windows Version

10.0.26200.9445

### User ID

670e1391-905a-4fe8-a9da-a22f01a4676c

### Log File

[debug.log](https://github.com/user-attachments/files/32248682/debug.log)

Reproduce the issue on Windows with WinAero Tweaker's File Explorer drive letters setting enabled, then trace the drive-name handling used by the rename flow. Confirm the fix by renaming a drive with its letter shown before the label and verifying that the letter is not duplicated.

Written by the indexing model from the issue text.