Remote Synchronization - Missing first letter of path for files/directory

### Apache NetBeans version

Apache NetBeans 19

### What happened

I tried to synchronize my files from a mapped network drive in Windows 11 to a FTP-Server and it fails because the first letter is always missing so the sync fails, here you have screenshots for better understanding:



I had this issue also in Netbeans 18 and tried to update to Netbeans 19, same problem.

### How to reproduce

_No response_

### Did this work correctly in an earlier version?

Apache NetBeans 14

### Operating System

Windows 11

### JDK

Java: 14.0.1; Java HotSpot(TM) 64-Bit Server VM 14.0.1+7

### Apache NetBeans packaging

Apache NetBeans provided installer

### Anything else

_No response_

### Are you willing to submit a pull request?

No

No source file, test, or entry point is named. Start by reproducing synchronization from a mapped Windows 11 network drive to an FTP server, comparing NetBeans 14 with 18 or 19. Done means the complete first path letter is preserved and synchronization succeeds.

Written by the indexing model from the issue text.