Exporting applications

**Describe the bug**
The action button "Export current selection XX" don't returns a message.

**Expected behavior**
I discover that the selection was exported to an .txt file.

**You have a solution?**
Maybe a popup with a message "xx lines was exported to /location/to/the/file.txt" is interesting :-)

Great job people!!

Look for the export functionality in the GUI code, likely in a Rust file handling button actions. Find where the export writes to a .txt file and add a popup message confirming the export with the line count and file path. Test the change by running the application and performing an export.

Written by the indexing model from the issue text.