Feature: Toast notifications for file operations

### What feature or improvement do you think would benefit Files?

Add Toast notifications support for file operations, display real-time progress notifications during file operations, and show alert notifications when completed or failed, so that Files can more prominently notify the user when in the background or minimized.

### Requirements

- This proposal will accomplish X
- This proposal will accomplish Y
- This proposal will accomplish Z

### Files Version

4.0.11

### Windows Version

26100.6584

### Comments

_No response_